MTGNexus

Animimicate Enchantment 3GW
Enchantment - Aura (R)
Enchant enchantment
During your turn, enchanted permanent becomes a 4/4 Spirit creature in addition to its other types.
Whenever enchanted permanent deals combat damage to a player, create a token copy of enchanted permanent, except its is a 4/4 Spirit creature with Indestructible in addition to its other types and abilities.

Looks fun! Two suggestions I would make:
-limit it to combat damage instead of all damage, so it doesn't trivially go infinite with any ETB damage effect (ex: Ghitu Journeymage)
-the token having indestructible when the original doesn't seems like it would cause a lot of memory issues

This should probably be "Enchant non-aura enchantment." I had to go look this up, but: an aura that becomes a creature falls off whatever it's enchanting and is put into the graveyard immediately after as as state-based action (similar to the rules about equipment becoming creatures, but equipment don't just detonate when they're not attached to anything, as we know already).

Aside from that, this is fairly interesting concept as a means of doubling enchantments.