Sometimes, more than one actor will occupy the same cell

[giovinazzo-kevin]

This is not strictly a bug because the game can handle it, but no two actors are supposed to share the same cell and as such some checks implemented as .Single() calls will fail.

[giovinazzo-kevin]

Also, while the game supports multiple items on the same tile without complaints, it's better for items to scatter around instead of piling up. So I should also fix any situation involving items piling up unintendedly.