anchor.diff:  	% Call the behavior
   	try apply(Behavior, Func, Args) of
   		{undefined, NewEntity1} ->
  -			NewEntity1;
  +			{noreply, NewEntity1};
   
   		{Update1, NewEntity2} ->
   			send_update(ClientInfo, EntityID, Update1),
  -			NewEntity2;
  +			{noreply, NewEntity2};
   
   		{Reply1, undefined, NewEntity3} ->
  -			{Reply1, NewEntity3};
  +			{reply, Reply1, NewEntity3};
   
   		{Reply2, Update2, NewEntity4} ->
   			send_update(ClientInfo, EntityID, Update2),
  -			{Reply2, NewEntity4}
  +			{reply, Reply2, NewEntity4}
   
   	catch
   		Exception ->
  
positive.code: 
  call_behavior_func(#entity{} = Entity, Func, Args, State) ->
  	case call_behavior_func(Entity, Func, Args) of
  		{Reply, NewEntity1} ->
  			{Reply, update_entity_state(NewEntity1, State)};
  		NewEntity2 ->
  			update_entity_state(NewEntity2, State)
  	end;
  
  call_behavior_func(EntityID, Func, Args, State) ->
  
negative.code: simulate_entities(State) ->
  	Entities = State#state.entities,
  	NewEntities = dict:map(fun(_EntityID, Entity) ->
  		{noreply, NewEntity} = call_behavior_func(Entity, simulate, [Entity, State]),
  		NewEntity
  	end, Entities),
  	State#state{
  		entities = NewEntities
  