you need a switch effect.
first case is an empty effect with allied building validator and default case is your normal effect chain.
if you want to stop attacking add a issue order effect with stop order
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you need 2 cases on your switch effect. one normal where allies is excluded and one where allies is included but buildings excluded, no default case. then you should not be able to attack allied buildings at all.
you need a switch effect. first case is an empty effect with allied building validator and default case is your normal effect chain.
if you want to stop attacking add a issue order effect with stop order
- - edit - -
you need 2 cases on your switch effect. one normal where allies is excluded and one where allies is included but buildings excluded, no default case. then you should not be able to attack allied buildings at all.