Beast Within
Instant
Destroy target permanent. Its controller creates a 3/3 green Beast creature token.
Beasties tend to be shy, kind to humans, and absolutely ruthless toward Valgavoth's monstrous spawn.
Jesper Ejsing
Rulings
If the target permanent is an illegal target by the time Beast Within tries to resolve, the spell won't resolve. No player creates a Beast token. If the target is legal but not destroyed (most likely because it has indestructible), its controller does create a Beast token.
(wotc • 2021-03-19)
If the permanent is still a legal target but is not destroyed (perhaps because it regenerated or has indestructible), its controller still gets the Beast token.
(wotc • 2013-07-01)
Printings
Rulings
If the target permanent is an illegal target by the time Beast Within tries to resolve, the spell won't resolve. No player creates a Beast token. If the target is legal but not destroyed (most likely because it has indestructible), its controller does create a Beast token.
(wotc • 2021-03-19)
If the permanent is still a legal target but is not destroyed (perhaps because it regenerated or has indestructible), its controller still gets the Beast token.
(wotc • 2013-07-01)