15mm figures. Instead of stacking figures I count all of them in contact, like a chain.
When entering a building I stack them in same hex, Survivors still fit. Zeds are placed in contact. If they could reach the hex the target occupies they melee. Their actual placement isn't important as zeds and humans won't end their turn in the same hex.
Zeds activate and all those that can reach the human will enter melee. This still is limited to 4, the number that can stack in the game
Melee. Remember that after melee there is one winner so they will not have to share the hex.
Same situation. Zeds activate but this time...
One zed can't reach the target hex so is not involved in the melee.
25mm minis from THW.