Dragon's Rage Channeler (9) [Modern Horizons 2 Timeshifts]

Whenever you cast a noncreature spell, surveil 1. (Look at the top card of your library. You may put that card into your graveyard.) Delirium — As long as there are four or more card types among cards in your graveyard, this creature gets +2/+2, has flying, and attacks each combat if able.