Hi Miguel! When using ClientEvents, try to make each event line up with a single input from the user. So, let’s say you have a button which can be clicked by the user to move north, and one button click always equals 10 “positions” on the map. The ClientEvent in this case would just be :move_north - and the distance moved is only a concern for the ClientEventHandler:

def Ship.Systems.ClientEventHandler do
  ...
  @move_distance 10

  defp process_one({player, :move_north}) do
    y = YPosition.get(player)
    YPosition.update(player, y + @move_distance)
  end
end

Now, if you have a button where sometimes a press moves 10 positions, and other times a press moves 5 positions, the question is: what determines this value? If the value comes from the frontend, such as a slider in the UI where the user adjusts the speed, then we’ll attach that value as metadata with the event:

ClientEvents.add(player_entity, {:move_north, 10})
ClientEvents.add(player_entity, {:move_north, 5})

and the handler:

defp process_one({player, {:move_north, value}}) do
  y = YPosition.get(player)
  YPosition.update(player, y + value)
end

But if the value is based in the backend (stored as a component somewhere) then metadata should not be used. For example, if one button press equals s positions, where s is the SailingSpeed of the player’s ship, simply add :move_north and fetch the value in the handler:

defp process_one({player, :move_north}) do
  y = YPosition.get(player)
  value = SailingSpeed.get(player)
  YPosition.update(player, y + value)
end

Hope this helps, happy to answer any other questions you might have!