The vortex ability probably creates a buff on the victim unit. You would just need to check whether 'x' unit has that buff. If it does, then it's in the vortex. If it does not, then it is not in the vortex.
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Malum Ruina: SC2Mapster
Eternal Exile: SC2Mapster
Spine Crawler Madness: SC2Mapster
Xeno Crisis: SC2Mapster
MoDTassadar Regular ShmoeHow do you detect when x unit has entered a vortex and when it gets out?
Thanks in advance! (As I am not experienced in this)