Activated Sleeper

Flash
You may have this creature enter as a copy of any creature card in a graveyard that was put there from the battlefield this turn, except it's a Phyrexian in addition to its other types.

Protection Magic

Put a shield counter on each of up to three target creatures. (If a creature with a shield counter would be dealt damage or destroyed, remove a shield counter from it instead.)

Olivia Voldaren

Flying
{1}{R}: Olivia Voldaren deals 1 damage to another target creature. That creature becomes a Vampire in addition to its other types. Put a +1/+1 counter on Olivia Voldaren.
{3}{B}{B}: Gain control of target Vampire for as long as you control Olivia Voldaren.

Shalai and Hallar

Flying, vigilance
Whenever one or more +1/+1 counters are put on a creature you control, Shalai and Hallar deals that much damage to target opponent.

Tempt with Discovery

Tempting offer — Search your library for a land card and put it onto the battlefield. Each opponent may search their library for a land card and put it onto the battlefield. For each opponent who searches a library this way, search your library for a land card and put it onto the battlefield. Then each player who searched a library this way shuffles.

Collective Effort

Escalate—Tap an untapped creature you control. (Pay this cost for each mode chosen beyond the first.)
Choose one or more —
• Destroy target creature with power 4 or greater.
• Destroy target enchantment.
• Put a +1/+1 counter on each creature target player controls.

Shalai, Voice of Plenty

Flying
You, planeswalkers you control, and other creatures you control have hexproof.
{4}{G}{G}: Put a +1/+1 counter on each creature you control.

Be'lakor, the Dark Master

Flying
Prince of Chaos — When Be'lakor, the Dark Master enters, you draw X cards and you lose X life, where X is the number of Demons you control.
Lord of Torment — Whenever another Demon you control enters, it deals damage equal to its power to any target.

Liliana's Triumph

Each opponent sacrifices a creature of their choice. If you control a Liliana planeswalker, each opponent also discards a card.