currypuff :
Don't compare... use picking conditions for picking...
Don't use this:
Distance(mine and enemy) less than or equal to 150 pixels.
Use this:
Pick (by comparison) : Enemy.X > Mine.X &
Pick (by comparison) : Enemy.X < or = Mine.X + 150
And also, use For Each
Complete event:
For Each (Enemy)
Pick (by comparison) : Enemy.X > Mine.X &
Pick (by comparison) : Enemy.X < or = Mine.X + 150
Mine pick nearest enemy.
Mine is not playing animation "active".
Then:
Mine set animation active (from beginning).
However this doesn't work when multiple mines are on-screen.
Or if it's too complicated for you, then use "Line of Sight"