diff --git a/examples/events_and_messages/cars.py b/examples/events_and_messages/cars.py
index 04d7894..c612f70 100644
--- a/examples/events_and_messages/cars.py
+++ b/examples/events_and_messages/cars.py
@@ -127,7 +127,8 @@ class Driver(Evented, FSM):
                 )
 
             self.check_passengers()
-            self.check_messages()  # This will call on_receive behind the scenes, and the agent's status will be updated
+            # This will call on_receive behind the scenes, and the agent's status will be updated
+            self.check_messages()  
             yield Delta(30)  # Wait at least 30 seconds before checking again
 
         try:
@@ -204,6 +205,8 @@ class Passenger(Evented, FSM):
         while not self.journey:
             self.info(f"Passenger at: { self.pos }. Checking for responses.")
             try:
+                # This will call check_messages behind the scenes, and the agent's status will be updated
+                # If you want to avoid that, you can call it with: check=False
                 yield self.received(expiration=expiration)
             except events.TimedOut:
                 self.info(f"Passenger at: { self.pos }. Asking for journey.")
@@ -211,7 +214,6 @@ class Passenger(Evented, FSM):
                     journey, ttl=timeout, sender=self, agent_class=Driver
                 )
                 expiration = self.now + timeout
-            self.check_messages()
         return self.driving_home
 
     @state
@@ -220,7 +222,11 @@ class Passenger(Evented, FSM):
             self.pos[0] != self.journey.destination[0]
             or self.pos[1] != self.journey.destination[1]
         ):
-            yield self.received(timeout=60)
+            try:
+                yield self.received(timeout=60)
+            except events.TimedOut:
+                pass
+
         self.info("Got home safe!")
         self.die()
 
diff --git a/examples/rabbits/basic/rabbit_agents.py b/examples/rabbits/basic/rabbit_agents.py
index b28d2e9..4c0981b 100644
--- a/examples/rabbits/basic/rabbit_agents.py
+++ b/examples/rabbits/basic/rabbit_agents.py
@@ -133,7 +133,7 @@ class RandomAccident(BaseAgent):
             math.log10(max(1, rabbits_alive))
         )
         self.debug("Killing some rabbits with prob={}!".format(prob_death))
-        for i in self.iter_agents(agent_class=Rabbit):
+        for i in self.get_agents(agent_class=Rabbit):
             if i.state_id == i.dead.id:
                 continue
             if self.prob(prob_death):
diff --git a/soil/agents/__init__.py b/soil/agents/__init__.py
index c13999f..a9c1fc3 100644
--- a/soil/agents/__init__.py
+++ b/soil/agents/__init__.py
@@ -20,12 +20,6 @@ from typing import Dict, List
 from .. import serialization, utils, time, config
 
 
-def as_node(agent):
-    if isinstance(agent, BaseAgent):
-        return agent.id
-    return agent
-
-
 IGNORED_FIELDS = ("model", "logger")
 
 
@@ -97,10 +91,6 @@ class BaseAgent(MesaAgent, MutableMapping, metaclass=MetaAgent):
     """
 
     def __init__(self, unique_id, model, name=None, interval=None, **kwargs):
-        # Check for REQUIRED arguments
-        # Initialize agent parameters
-        if isinstance(unique_id, MesaAgent):
-            raise Exception()
         assert isinstance(unique_id, int)
         super().__init__(unique_id=unique_id, model=model)
 
@@ -207,7 +197,8 @@ class BaseAgent(MesaAgent, MutableMapping, metaclass=MetaAgent):
     def step(self):
         if not self.alive:
             raise time.DeadAgent(self.unique_id)
-        return super().step() or time.Delta(self.interval)
+        super().step() 
+        return time.Delta(self.interval)
 
     def log(self, message, *args, level=logging.INFO, **kwargs):
         if not self.logger.isEnabledFor(level):
@@ -270,6 +261,7 @@ def prob(prob, random):
     return r < prob
 
 
+
 def calculate_distribution(network_agents=None, agent_class=None):
     """
     Calculate the threshold values (thresholds for a uniform distribution)
@@ -414,7 +406,7 @@ def filter_agents(
     if ids:
         f = (agents[aid] for aid in ids if aid in agents)
     else:
-        f = (a for a in agents.values())
+        f = agents.values()
 
     if state_id is not None and not isinstance(state_id, (tuple, list)):
         state_id = tuple([state_id])
@@ -638,6 +630,10 @@ from .SentimentCorrelationModel import *
 from .SISaModel import *
 from .CounterModel import *
 
+
+class Agent(NetworkAgent, EventedAgent):
+    '''Default agent class, has both network and event capabilities'''
+
 try:
     import scipy
     from .Geo import Geo
diff --git a/soil/agents/evented.py b/soil/agents/evented.py
index 451b570..340c29a 100644
--- a/soil/agents/evented.py
+++ b/soil/agents/evented.py
@@ -1,57 +1,74 @@
 from . import BaseAgent
-from ..events import Message, Tell, Ask, Reply, TimedOut
-from ..time import Cond
+from ..events import Message, Tell, Ask, TimedOut
+from ..time import BaseCond
 from functools import partial
 from collections import deque
 
 
-class Evented(BaseAgent):
+class ReceivedOrTimeout(BaseCond):
+    def __init__(self, agent, expiration=None, timeout=None, check=True, ignore=False, **kwargs):
+        if expiration is None:
+            if timeout is not None:
+                expiration = agent.now + timeout
+        self.expiration = expiration
+        self.ignore = ignore
+        self.check = check
+        super().__init__(**kwargs)
+
+    def expired(self, time):
+        return self.expiration and self.expiration < time
+
+    def ready(self, agent, time):
+        return len(agent._inbox) or self.expired(time)
+
+    def return_value(self, agent):
+        if not self.ignore and self.expired(agent.now):
+            raise TimedOut('No messages received')
+        if self.check:
+            agent.check_messages()
+        return None
+
+    def schedule_next(self, time, delta, first=False):
+        if self._delta is not None:
+            delta = self._delta
+        return (time + delta, self)
+
+    def __repr__(self):
+        return f'ReceivedOrTimeout(expires={self.expiration})'
+
+
+class EventedAgent(BaseAgent):
     def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
         self._inbox = deque()
-        self._received = 0
         self._processed = 0
 
-
     def on_receive(self, *args, **kwargs):
         pass
 
-    def received(self, expiration=None, timeout=None):
-        current = self._received
-        if expiration is None:
-            expiration = float('inf') if timeout is None else self.now + timeout
+    def received(self, *args, **kwargs):
+        return ReceivedOrTimeout(self, *args, **kwargs)
 
-        if expiration < self.now:
-            raise ValueError("Invalid expiration time")
-
-        def ready(agent):
-            return agent._received > current or agent.now >= expiration
-
-        def value(agent):
-            if agent.now > expiration:
-                raise TimedOut("No message received")
-
-        c = Cond(func=ready, return_func=value)
-        c._checked = True
-        return c
-
-    def tell(self, msg, sender):
-        self._received += 1
-        self._inbox.append(Tell(payload=msg, sender=sender))
+    def tell(self, msg, sender=None):
+        self._inbox.append(Tell(timestamp=self.now, payload=msg, sender=sender))
 
     def ask(self, msg, timeout=None):
-        self._received += 1
-        ask = Ask(payload=msg)
+        ask = Ask(timestamp=self.now, payload=msg)
         self._inbox.append(ask)
         expiration = float('inf') if timeout is None else self.now + timeout
         return ask.replied(expiration=expiration)
 
     def check_messages(self):
+        changed = False
         while self._inbox:
             msg = self._inbox.popleft()
             self._processed += 1
             if msg.expired(self.now):
                 continue
+            changed = True
             reply = self.on_receive(msg.payload, sender=msg.sender)
             if isinstance(msg, Ask):
                 msg.reply = reply
+        return changed
+
+Evented = EventedAgent
diff --git a/soil/agents/network_agents.py b/soil/agents/network_agents.py
index d9950cf..cd57943 100644
--- a/soil/agents/network_agents.py
+++ b/soil/agents/network_agents.py
@@ -54,7 +54,7 @@ class NetworkAgent(BaseAgent):
         return G
 
     def remove_node(self):
-        print(f"Removing node for {self.unique_id}: {self.node_id}")
+        self.debug(f"Removing node for {self.unique_id}: {self.node_id}")
         self.G.remove_node(self.node_id)
         self.node_id = None
 
@@ -80,3 +80,5 @@ class NetworkAgent(BaseAgent):
         if remove:
             self.remove_node()
         return super().die()
+
+NetAgent = NetworkAgent
diff --git a/soil/environment.py b/soil/environment.py
index 3a48d30..4be1625 100644
--- a/soil/environment.py
+++ b/soil/environment.py
@@ -310,17 +310,20 @@ class NetworkEnvironment(BaseEnvironment):
             self.add_agent(node_id=node_id, agent_class=a_class, **agent_params)
 
 
-Environment = NetworkEnvironment
-
-
-class EventedEnvironment(Environment):
-    def broadcast(self, msg,  sender, expiration=None, ttl=None, **kwargs):
+class EventedEnvironment(BaseEnvironment):
+    def broadcast(self, msg,  sender=None, expiration=None, ttl=None, **kwargs):
         for agent in self.agents(**kwargs):
+            if agent == sender:
+                continue
             self.logger.info(f'Telling {repr(agent)}: {msg} ttl={ttl}')
             try:
                 inbox = agent._inbox
             except AttributeError:
                 self.logger.info(f'Agent {agent.unique_id} cannot receive events because it does not have an inbox')
                 continue
+            # Allow for AttributeError exceptions in this part of the code
             inbox.append(events.Tell(payload=msg, sender=sender, expiration=expiration if ttl is None else self.now+ttl))
 
+
+class Environment(NetworkEnvironment, EventedEnvironment):
+    '''Default environment class, has both network and event capabilities'''
diff --git a/soil/events.py b/soil/events.py
index 3bc50eb..25f471a 100644
--- a/soil/events.py
+++ b/soil/events.py
@@ -1,4 +1,4 @@
-from .time import Cond
+from .time import BaseCond
 from dataclasses import dataclass, field
 from typing import Any
 from uuid import uuid4
@@ -11,6 +11,7 @@ class Message:
     payload: Any
     sender: Any = None
     expiration: float = None
+    timestamp: float = None
     id: int = field(default_factory=uuid4)
 
     def expired(self, when):
@@ -20,19 +21,28 @@ class Reply(Message):
     source: Message
 
 
+class ReplyCond(BaseCond):
+    def __init__(self, ask, *args, **kwargs):
+        self._ask = ask
+        super().__init__(*args, **kwargs)
+
+    def ready(self, agent, time):
+        return self._ask.reply is not None or self._ask.expired(time)
+
+    def return_value(self, agent):
+        if self._ask.expired(agent.now):
+            raise TimedOut()
+        return self._ask.reply
+
+    def __repr__(self):
+        return f"ReplyCond({self._ask.id})"
+
+
 class Ask(Message):
     reply: Message = None
 
     def replied(self, expiration=None):
-        def ready(agent):
-            return self.reply is not None or agent.now > expiration
-
-        def value(agent):
-            if agent.now > expiration:
-                raise TimedOut(f'No answer received for {self}')
-            return self.reply
-
-        return Cond(func=ready, return_func=value)
+        return ReplyCond(self)
 
 
 class Tell(Message):
diff --git a/soil/network.py b/soil/network.py
index be7d96f..a717021 100644
--- a/soil/network.py
+++ b/soil/network.py
@@ -59,7 +59,6 @@ def find_unassigned(G, shuffle=False, random=random):
 
     If node_id is None, a node without an agent_id will be found.
     """
-    # TODO: test
     candidates = list(G.nodes(data=True))
     if shuffle:
         random.shuffle(candidates)
diff --git a/soil/serialization.py b/soil/serialization.py
index f0a98df..cd34a02 100644
--- a/soil/serialization.py
+++ b/soil/serialization.py
@@ -221,8 +221,6 @@ def deserialize(type_, value=None, globs=None, **kwargs):
 
 def deserialize_all(names, *args, known_modules=KNOWN_MODULES, **kwargs):
     """Return the list of deserialized objects"""
-    # TODO: remove
-    print("SERIALIZATION", kwargs)
     objects = []
     for name in names:
         mod = deserialize(name, known_modules=known_modules)
diff --git a/soil/simulation.py b/soil/simulation.py
index 5746e67..75947de 100644
--- a/soil/simulation.py
+++ b/soil/simulation.py
@@ -66,7 +66,7 @@ class Simulation:
         if ignored:
             d.setdefault("extra", {}).update(ignored)
         if ignored:
-            print(f'Warning: Ignoring these parameters (added to "extra"): { ignored }')
+            logger.warning(f'Ignoring these parameters (added to "extra"): { ignored }')
         d.update(kwargs)
 
         return cls(**d)
diff --git a/soil/time.py b/soil/time.py
index ec1dc02..7e11201 100644
--- a/soil/time.py
+++ b/soil/time.py
@@ -1,10 +1,11 @@
 from mesa.time import BaseScheduler
 from queue import Empty
-from heapq import heappush, heappop, heapify
+from heapq import heappush, heappop
 import math
 
 from inspect import getsource
 from numbers import Number
+from textwrap import dedent
 
 from .utils import logger
 from mesa import Agent as MesaAgent
@@ -23,65 +24,11 @@ class When:
             return time
         self._time = time
 
-    def next(self, time):
+    def abs(self, time):
         return self._time
 
-    def abs(self, time):
-        return self
-
-    def __repr__(self):
-        return str(f"When({self._time})")
-
-    def __lt__(self, other):
-        if isinstance(other, Number):
-            return self._time < other
-        return self._time < other.next(self._time)
-
-    def __gt__(self, other):
-        if isinstance(other, Number):
-            return self._time > other
-        return self._time > other.next(self._time)
-
-    def ready(self, agent):
-        return self._time <= agent.model.schedule.time
-
-    def return_value(self, agent):
-        return None
-
-
-class Cond(When):
-    def __init__(self, func, delta=1, return_func=lambda agent: None):
-        self._func = func
-        self._delta = delta
-        self._checked = False
-        self._return_func = return_func
-
-    def next(self, time):
-        if self._checked:
-            return time + self._delta
-        return time
-
-    def abs(self, time):
-        return self
-
-    def ready(self, agent):
-        self._checked = True
-        return self._func(agent)
-
-    def return_value(self, agent):
-        return self._return_func(agent)
-
-    def __eq__(self, other):
-        return False
-
-    def __lt__(self, other):
-        return True
-
-    def __gt__(self, other):
-        return False
-
-    def __repr__(self):
-        return str(f'Cond("{getsource(self._func)}")')
+    def schedule_next(self, time, delta, first=False):
+        return (self._time, None)
 
 
 NEVER = When(INFINITY)
@@ -91,48 +38,94 @@ class Delta(When):
     def __init__(self, delta):
         self._delta = delta
 
+    def abs(self, time):
+        return self._time + self._delta
+
     def __eq__(self, other):
         if isinstance(other, Delta):
             return self._delta == other._delta
         return False
 
-    def abs(self, time):
-        return When(self._delta + time)
-
-    def next(self, time):
-        return time + self._delta
+    def schedule_next(self, time, delta, first=False):
+        return (time + self._delta, None)
 
     def __repr__(self):
         return str(f"Delta({self._delta})")
 
 
+class BaseCond:
+    def __init__(self, msg=None, delta=None, eager=False):
+        self._msg = msg
+        self._delta = delta
+        self.eager = eager
+
+    def schedule_next(self, time, delta, first=False):
+        if first and self.eager:
+            return (time, self)
+        if self._delta:
+            delta = self._delta
+        return (time + delta, self)
+
+    def return_value(self, agent):
+        return None
+
+    def __repr__(self):
+        return self._msg or self.__class__.__name__
+
+
+class Cond(BaseCond):
+    def __init__(self, func, *args, **kwargs):
+        self._func = func
+        super().__init__(*args, **kwargs)
+
+    def ready(self, agent, time):
+        return self._func(agent)
+
+    def __repr__(self):
+        if self._msg:
+            return self._msg
+        return str(f'Cond("{dedent(getsource(self._func)).strip()}")')
+
+
 class TimedActivation(BaseScheduler):
     """A scheduler which activates each agent when the agent requests.
     In each activation, each agent will update its 'next_time'.
     """
 
-    def __init__(self, *args, **kwargs):
+    def __init__(self, *args, shuffle=True, **kwargs):
         super().__init__(*args, **kwargs)
         self._next = {}
         self._queue = []
-        self.next_time = 0
+        self._shuffle = shuffle
+        self.step_interval = 1
         self.logger = logger.getChild(f"time_{ self.model }")
 
     def add(self, agent: MesaAgent, when=None):
         if when is None:
-            when = When(self.time)
-        elif not isinstance(when, When):
-            when = When(when)
-        if agent.unique_id in self._agents:
-            del self._agents[agent.unique_id]
-            if agent.unique_id in self._next:
-                self._queue.remove((self._next[agent.unique_id], agent))
-                heapify(self._queue)
-
-        self._next[agent.unique_id] = when
-        heappush(self._queue, (when, agent))
+            when = self.time
+        elif isinstance(when, When):
+            when = when.abs()
+            
+        self._schedule(agent, None, when)
         super().add(agent)
 
+    def _schedule(self, agent, condition=None, when=None):
+        if condition:
+            if not when:
+                when, condition = condition.schedule_next(when or self.time,
+                                                          self.step_interval)
+        else:
+            if when is None:
+                when = self.time + self.step_interval
+            condition = None
+        if self._shuffle:
+            key = (when, self.model.random.random(), condition)
+        else:
+            key = (when, agent.unique_id, condition)
+        self._next[agent.unique_id] = key
+        heappush(self._queue, (key, agent))
+
+
     def step(self) -> None:
         """
         Executes agents in order, one at a time. After each step,
@@ -143,73 +136,59 @@ class TimedActivation(BaseScheduler):
         if not self.model.running:
             return
 
-        when = NEVER
-
-        to_process = []
-        skipped = []
-        next_time = INFINITY
-
-        ix = 0
-
         self.logger.debug(f"Queue length: {len(self._queue)}")
 
         while self._queue:
-            (when, agent) = self._queue[0]
+            ((when, _id, cond), agent) = self._queue[0]
             if when > self.time:
                 break
+
             heappop(self._queue)
-            if when.ready(agent):
+            if cond:
+                if not cond.ready(agent, self.time):
+                    self._schedule(agent, cond)
+                    continue
                 try:
-                    agent._last_return = when.return_value(agent)
+                    agent._last_return = cond.return_value(agent)
                 except Exception as ex:
                     agent._last_except = ex
+            else:
+                agent._last_return = None
+                agent._last_except = None
 
-                self._next.pop(agent.unique_id, None)
-                to_process.append(agent)
-                continue
-
-            next_time = min(next_time, when.next(self.time))
-            self._next[agent.unique_id] = next_time
-            skipped.append((when, agent))
-
-        if self._queue:
-            next_time = min(next_time, self._queue[0][0].next(self.time))
-
-        self._queue = [*skipped, *self._queue]
-
-        for agent in to_process:
             self.logger.debug(f"Stepping agent {agent}")
+            self._next.pop(agent.unique_id, None)
 
             try:
-                returned = ((agent.step() or Delta(1))).abs(self.time)
+                returned = agent.step()
             except DeadAgent:
-                if agent.unique_id in self._next:
-                    del self._next[agent.unique_id]
                 agent.alive = False
                 continue
 
+            # Check status for MESA agents
             if not getattr(agent, "alive", True):
                 continue
 
-            value = returned.next(self.time)
-            agent._last_return = value
-
-            if value < self.time:
-                raise Exception(
-                    f"Cannot schedule an agent for a time in the past ({when} < {self.time})"
-                )
-            if value < INFINITY:
-                next_time = min(value, next_time)
-
-                self._next[agent.unique_id] = returned
-                heappush(self._queue, (returned, agent))
+            if returned:
+                next_check = returned.schedule_next(self.time, self.step_interval, first=True)
+                self._schedule(agent, when=next_check[0], condition=next_check[1])
             else:
-                assert not self._next[agent.unique_id]
+                next_check = (self.time + self.step_interval, None)
+
+                self._schedule(agent)
 
         self.steps += 1
-        self.logger.debug(f"Updating time step: {self.time} -> {next_time}")
-        self.time = next_time
 
-        if not self._queue or next_time == INFINITY:
+        if not self._queue:
+            self.time = INFINITY
             self.model.running = False
             return self.time
+
+        next_time = self._queue[0][0][0]
+        if next_time < self.time:
+            raise Exception(
+                f"An agent has been scheduled for a time in the past, there is probably an error ({when} < {self.time})"
+            )
+        self.logger.debug(f"Updating time step: {self.time} -> {next_time}")
+
+        self.time = next_time
diff --git a/tests/test_agents.py b/tests/test_agents.py
index c6a603e..a32d91a 100644
--- a/tests/test_agents.py
+++ b/tests/test_agents.py
@@ -12,12 +12,11 @@ class Dead(agents.FSM):
         return self.die()
 
 
-class TestMain(TestCase):
+class TestAgents(TestCase):
     def test_die_returns_infinity(self):
         '''The last step of a dead agent should return time.INFINITY'''
         d = Dead(unique_id=0, model=environment.Environment())
-        ret = d.step().abs(0)
-        print(ret, "next")
+        ret = d.step()
         assert ret == stime.NEVER
 
     def test_die_raises_exception(self):
@@ -66,4 +65,95 @@ class TestMain(TestCase):
         a.step()
         assert a.run == 1
         a.step()
-        assert a.run == 2
+
+
+    def test_broadcast(self):
+        '''
+        An agent should be able to broadcast messages to every other agent, AND each receiver should be able
+        to process it
+        '''
+        class BCast(agents.Evented):
+            pings_received = 0
+
+            def step(self):
+                print(self.model.broadcast)
+                try:
+                    self.model.broadcast('PING')
+                except Exception as ex:
+                    print(ex)
+                while True:
+                    self.check_messages()
+                    yield
+
+            def on_receive(self, msg, sender=None):
+                self.pings_received += 1
+        
+        e = environment.EventedEnvironment()
+
+        for i in range(10):
+            e.add_agent(agent_class=BCast)
+        e.step()
+        pings_received = lambda: [a.pings_received for a in e.agents]
+        assert sorted(pings_received()) == list(range(1, 11))
+        e.step()
+        assert all(x==10 for x in pings_received())
+
+    def test_ask_messages(self):
+        '''
+        An agent should be able to ask another agent, and wait for a response.
+        '''
+
+        # #Results depend on ordering (agents are shuffled), so force the first agent
+        pings = []
+        pongs = []
+        responses = []
+
+        class Ping(agents.EventedAgent):
+            def step(self):
+                target_id = (self.unique_id + 1) % self.count_agents()
+                target = self.model.agents[target_id]
+                print('starting')
+                while True:
+                    print('Pings: ', pings, responses or not pings, self.model.schedule._queue)
+                    if pongs or not pings:
+                        pings.append(self.now)
+                        response = yield target.ask('PING')
+                        responses.append(response)
+                    else:
+                        print('NOT sending ping')
+                    print('Checking msgs')
+                    # Do not advance until we have received a message.
+                    # warning: it will wait at least until the next time in the simulation
+                    yield self.received(check=True)
+                print('done')
+
+            def on_receive(self, msg, sender=None):
+                if msg == 'PING':
+                    pongs.append(self.now)
+                    return 'PONG'
+
+        e = environment.EventedEnvironment()
+        for i in range(2):
+            e.add_agent(agent_class=Ping)
+        assert e.now == 0
+
+        # There should be a delay of one step between agent 0 and 1
+        # On the first step:
+        #   Agent 0 sends a PING, but blocks before a PONG
+        #   Agent 1 sends a PONG, and blocks after its PING
+        # After that step, every agent can both receive (there are pending messages) and then send.
+
+        e.step()
+        assert e.now == 1
+        assert pings == [0]
+        assert pongs == []
+
+        e.step()
+        assert e.now == 2
+        assert pings == [0, 1]
+        assert pongs == [1]
+
+        e.step()
+        assert e.now == 3
+        assert pings == [0, 1, 2]
+        assert pongs == [1, 2]
diff --git a/tests/test_examples.py b/tests/test_examples.py
index a0a2bd5..b2d2750 100644
--- a/tests/test_examples.py
+++ b/tests/test_examples.py
@@ -44,6 +44,8 @@ def add_example_tests():
     for cfg, path in serialization.load_files(
         join(EXAMPLES, "**", "*.yml"),
     ):
+        if 'soil_output' in path:
+            continue
         p = make_example_test(path=path, cfg=config.Config.from_raw(cfg))
         fname = os.path.basename(path)
         p.__name__ = "test_example_file_%s" % fname
diff --git a/tests/test_main.py b/tests/test_main.py
index 8f4f97c..d100b97 100644
--- a/tests/test_main.py
+++ b/tests/test_main.py
@@ -172,25 +172,21 @@ class TestMain(TestCase):
         assert len(configs) > 0
 
     def test_until(self):
-        config = {
-            "name": "until_sim",
-            "model_params": {
-                "network_params": {},
-                "agents": {
-                    "fixed": [
-                        {
-                            "agent_class": agents.BaseAgent,
-                        }
-                    ]
-                },
-            },
-            "max_time": 2,
-            "num_trials": 50,
-        }
-        s = simulation.from_config(config)
+        n_runs = 0
+
+        class CheckRun(agents.BaseAgent):
+            def step(self):
+                nonlocal n_runs
+                n_runs += 1
+                return super().step()
+
+        n_trials = 50
+        max_time = 2
+        s = simulation.Simulation(model_params={'agents': [{'agent_class': CheckRun}]},
+                                  num_trials=n_trials, max_time=max_time)
         runs = list(s.run_simulation(dry_run=True))
         over = list(x.now for x in runs if x.now > 2)
-        assert len(runs) == config["num_trials"]
+        assert len(runs) == n_trials
         assert len(over) == 0
 
     def test_fsm(self):
diff --git a/tests/test_network.py b/tests/test_network.py
index a860b14..89ff4a0 100644
--- a/tests/test_network.py
+++ b/tests/test_network.py
@@ -72,7 +72,7 @@ class TestNetwork(TestCase):
         assert len(env.agents) == 2
         assert env.agents[1].count_agents(state_id="normal") == 2
         assert env.agents[1].count_agents(state_id="normal", limit_neighbors=True) == 1
-        assert env.agents[0].neighbors == 1
+        assert env.agents[0].count_neighbors() == 1
 
     def test_custom_agent_neighbors(self):
         """Allow for search of neighbors with a certain state_id"""
@@ -90,7 +90,7 @@ class TestNetwork(TestCase):
         env = s.run_simulation(dry_run=True)[0]
         assert env.agents[1].count_agents(state_id="normal") == 2
         assert env.agents[1].count_agents(state_id="normal", limit_neighbors=True) == 1
-        assert env.agents[0].neighbors == 1
+        assert env.agents[0].count_neighbors() == 1
 
     def test_subgraph(self):
         """An agent should be able to subgraph the global topology"""
diff --git a/tests/test_time.py b/tests/test_time.py
index db16609..458b734 100644
--- a/tests/test_time.py
+++ b/tests/test_time.py
@@ -30,8 +30,9 @@ class TestMain(TestCase):
 
         times_started = []
         times_awakened = []
+        times_asleep = []
         times = []
-        done = 0
+        done = []
 
         class CondAgent(agents.BaseAgent):
 
@@ -39,36 +40,38 @@ class TestMain(TestCase):
                 nonlocal done
                 times_started.append(self.now)
                 while True:
-                    yield time.Cond(lambda agent: agent.model.schedule.time >= 10)
+                    times_asleep.append(self.now)
+                    yield time.Cond(lambda agent: agent.now >= 10,
+                                    delta=2)
                     times_awakened.append(self.now)
                     if self.now >= 10:
                         break
-                done += 1
+                done.append(self.now)
 
         env = environment.Environment(agents=[{'agent_class': CondAgent}])
 
 
         while env.schedule.time < 11:
-            env.step()
             times.append(env.now)
+            env.step()
+
         assert env.schedule.time == 11
         assert times_started == [0]
         assert times_awakened == [10]
-        assert done == 1
+        assert done == [10]
         # The first time will produce the Cond.
-        # Since there are no other agents, time will not advance, but the number
-        # of steps will.
-        assert env.schedule.steps == 12
-        assert len(times) == 12
+        assert env.schedule.steps == 6
+        assert len(times) == 6
 
-        while env.schedule.time < 12:
-            env.step()
+        while env.schedule.time < 13:
             times.append(env.now)
+            env.step()
 
-        assert env.schedule.time == 12
+        assert times == [0, 2, 4, 6, 8, 10, 11]
+        assert env.schedule.time == 13
         assert times_started == [0, 11]
-        assert times_awakened == [10, 11]
-        assert done == 2
+        assert times_awakened == [10]
+        assert done == [10]
         # Once more to yield the cond, another one to continue
-        assert env.schedule.steps == 14
-        assert len(times) == 14
+        assert env.schedule.steps == 7
+        assert len(times) == 7