I think the point Drobbit is subtley making is cards like fractal have high costs for a reason. Allowing a creature to gain those high cost spells as an ability is way too imbalancing and OP.
That's it. I think that some spells can not be abbilities.
Nova-supernova=unlimited mana. You won't need towers anymore. Just this creature
Blessing: you won't need growing creatures, this grow them
Holy light: no need of any other healing card
and many more spells... that's why I think this card is not a good idea. Sorry
Nova | Supernova doesn't target creatures. No way for it to do that.
I'll try to make a list of all abilities this guy can have.
Infection (Bloodsuckers, etc.)
Blessing
Holy Light
Fractal
TU
Thunderbolt
Thunderstorm
Unstable Gas (wouldn't it just gain the Ignite ability? no bueno!)
Siphon Life
Chaos Power (Chaos Seed might give it various abilities including sniper, siphon, etc., unless it was set to gain Chaos Seed)
Sniper
AM (or Nymph's cost)
Pandemonium
Would Retrovirus give him the sacrifice ability? :O
Plague (*screams*)
Aflatoxin (or Nymph's cost)
Momentum
Gravity Force
Plate Armor
BB (or petrify)
Adrenaline
Fire Bolt
Rain of Fire (*screams*)
Rage Potion (or rage)
Luciferin (or Nymph's cost)
Inflate
Freeze (or Arctic Squad's cost)
Ice Bolt
Shockwave
Quintessence (or Nymph's/Anubis' cost)
Liquid Shadow (or Nymph's cost) (a pain, since when you use it, it removes its ability to gain any more skills)
Nightmare (. . . it does target the creature, but... Nightmare? as an active ability? can you say hand control?)
Shard of Readiness (no freaking way)
That's an interesting card, seeing as how it can, at any time, become any of the above abilities. (and yes, I made sure these were all the abilities possible to be put on Copycat)