Priest of Gix

When this creature enters, add {B}{B}{B}.

Kiki-Jiki, Mirror Breaker

Haste
{T}: Create a token that's a copy of target nonlegendary creature you control, except it has haste. Sacrifice it at the beginning of the next end step.

Heartless Hidetsugu

{T}: Heartless Hidetsugu deals damage to each player equal to half that player's life total, rounded down.

Mogg Fanatic

Sacrifice this creature: It deals 1 damage to any target.

Necrotic Ooze

As long as this creature is on the battlefield, it has all activated abilities of all creature cards in all graveyards.

Final Parting

Search your library for two cards. Put one into your hand and the other into your graveyard. Then shuffle.

Priest of Urabrask

When this creature enters, add {R}{R}{R}.

Buried Alive

Search your library for up to three creature cards, put them into your graveyard, then shuffle.

Death Cultist

Sacrifice this creature: Target player loses 1 life and you gain 1 life.

Obosh, the Preypiercer

Companion — Your starting deck contains only cards with odd mana values and land cards. (If this card is your chosen companion, you may put it into your hand from outside the game for {3} as a sorcery.)
If a source you control with an odd mana value would deal damage to a permanent or player, it deals double that damage to that permanent or player instead.

Florian, Voldaren Scion

First strike
At the beginning of each of your postcombat main phases, look at the top X cards of your library, where X is the total amount of life your opponents lost this turn. Exile one of those cards and put the rest on the bottom of your library in a random order. You may play the exiled card this turn.