Helvault

This artifact enters tapped. T: Add two mana in any combination of colors. Spend this mana only to cast spells with flashback from a graveyard.

At the beginning of each upkeep, if no spells were cast last turn, transform this creature.

Return target creature you own to your hand. Flashback W (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Discard all the cards in your hand, then draw that many cards. Flashback 5R (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Trample Morbid — This creature enters with four +1/+1 counters on it if a creature died this turn.

Enchant player At the beginning of your upkeep, you may search your library for a Curse card that doesn't have the same name as a Curse attached to enchanted player, put it onto the battlefield attached to that player, then shuffle.

Flying This creature can block only creatures with flying. Undying (When this creature dies, if it had no +1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it.)

Reveal the top four cards of your library. Put a creature card from among them into your hand and the rest into your graveyard. Flashback 2U (You may cast this card from your graveyard for its flashback cost. Then exile it.)