You appear to be using the damage effect in the Unit - Unit - Effect field. This is changing the scope of reference for your target to the target of an effect that has not yet occured. Also consider giving it a default button.
How I would do the ability is to have Effect - Instant/Target ability linked to a Search Area effect that then uses an Apply Behavior effect to apply a Buff behaviour. The buff then has negative life regeneration or a periodic damage effect.
You appear to be using the damage effect in the Unit - Unit - Effect field. This is changing the scope of reference for your target to the target of an effect that has not yet occured. Also consider giving it a default button.
How I would do the ability is to have Effect - Instant/Target ability linked to a Search Area effect that then uses an Apply Behavior effect to apply a Buff behaviour. The buff then has negative life regeneration or a periodic damage effect.
Contribute to the wiki (Wiki button at top of page) Considered easy altering of the unit textures?
https://www.sc2mapster.com/forums/resources/tutorials/179654-data-actor-events-message-texture-select-by-id
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