Thats not until the end of the turn, or until the spell gets exiled from your graveyard or something
Seven mana to transform this into Hydaelyn, the Mothercrystal is a lot, but well worth it
Play Lion Heart with him in play, and you get not only a gunblade, but a twincast Shock
You want to control the board by eliminating every card your opponent plays, and Dragon Fire allows you to get rid of a high-value target that would otherwise be difficult to Challenge down
Urza, Chief Artificer Most of the time, youll be casting Urza, Chief Artificer just for 3 mana, thanks to its affinity ability, and while giving menace to other artifact creatures is nice, Id have loved for its final ability to be triggered on ETB rather than at your end step so you can blink it and endlessly create an army