Not sure which kind of deck would play it.. it's too weak for a control deck, and aggro deck don't run many expensive spells normally (you need around 6 to activate it consistently as seen in WOG dragon warrior)
3-mana 4/4s are good in tempo decks, but holding a large spell typically is bad for a tempo deck. Maybe there are cards such as Lesser Emerald Spellstone that it works with, but there's probably better centers for deckbuilding.
This looks really strong on curve but i’m not sure what kind of tempo deck can consistently play this. Tempo decks don’t play 5 Mana spells so even though it has a ton of potential it probably won’t see play.