Phyrexian Fleshgorger

Prototype {1}{B}{B} — 3/3 (You may cast this spell with different mana cost, color, and size. It keeps its abilities and types.)
Menace, lifelink
Ward—Pay life equal to Phyrexian Fleshgorger's power.

Doomsday Excruciator

Flying
When Doomsday Excruciator enters, if it was cast, each player exiles all but the bottom six cards of their library face down.
At the beginning of your upkeep, draw a card.

Hidetsugu, Devouring Chaos

{B}, Sacrifice a creature: Scry 2.
{2}{R}, {T}: Exile the top card of your library. You may play that card this turn. When you exile a nonland card this way, Hidetsugu, Devouring Chaos deals damage equal to the exiled card's mana value to any target.

Blood for the Blood God!

This spell costs {1} less to cast for each creature that died this turn.
Discard your hand, then draw eight cards. Blood for the Blood God! deals 8 damage to each opponent. Exile Blood for the Blood God!

Goring Warplow

Prototype {1}{B} — 1/1 (You may cast this spell with different mana cost, color, and size. It keeps its abilities and types.)
Deathtouch

Etali, Primal Storm

Whenever Etali attacks, exile the top card of each player's library, then you may cast any number of spells from among those cards without paying their mana costs.

Shadow of Mortality

If your life total is less than your starting life total, this spell costs {X} less to cast, where X is the difference.

Skitterbeam Battalion

Prototype {3}{R}{R} — 2/2 (You may cast this spell with different mana cost, color, and size. It keeps its abilities and types.)
Trample, haste
When Skitterbeam Battalion enters, if you cast it, create two tokens that are copies of it.

Frogmyr Enforcer

Prototype {3}{R} — 2/2 (You may cast this spell with different mana cost, color, and size. It keeps its abilities and types.)
Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)

Fallaji Dragon Engine

Prototype {2}{R} — 1/3 (You may cast this spell with different mana cost, color, and size. It keeps its abilities and types.)
Flying
{2}: Fallaji Dragon Engine gets +1/+0 until end of turn.

Kaervek the Merciless

Whenever an opponent casts a spell, Kaervek the Merciless deals damage equal to that spell's mana value to any target.

Volcanic Salvo

This spell costs {X} less to cast, where X is the total power of creatures you control.
Volcanic Salvo deals 6 damage to each of up to two target creatures and/or planeswalkers.

Blitz Automaton

Prototype {2}{R} — 3/2 (You may cast this spell with different mana cost, color, and size. It keeps its abilities and types.)
Haste