TRIGGER 1: ----Ammo decrease
EVENT: unit-a unit is attacked
CONDITION: <<< here conditions that only those players decrease ammo, which use ammo >>>
---for example---
OR
- (owner of attacking unit) equal to player X
- (owner of attacking unit) equal to player Y
ACTIONS: add -1 lumber to (owner of attacking unit)
TRIGGER 2: ---If Ammo 0---
EVENT: (player X) lumber less than or equal to 0
(player Y) lumber less than or equal to 0
...
COND:
ACTIONS: set (triggering player) alliance to player(enemy) to neutral
TRIGGER 3: ---Has ammo again---
EVENT: (player X) lumber becomes greater than 0
(player Y) lumber becomes greater than 0
...
COND:
ACTIONS: set (triggering player) alliance to player(enemy) to enemy