Wild Dogs

At the beginning of your upkeep, if a player has more life than each other player, the player with the most life gains control of Wild Dogs.
Cycling {2} ({2}, Discard this card: Draw a card.)

Act of Authority

When Act of Authority enters, you may exile target artifact or enchantment.
At the beginning of your upkeep, you may exile target artifact or enchantment. If you do, its controller gains control of Act of Authority.

Ghazbán Ogre

At the beginning of your upkeep, if a player has more life than each other player, the player with the most life gains control of Ghazbán Ogre.

Dubious Challenge

Look at the top ten cards of your library, exile up to two creature cards from among them, then shuffle. Target opponent may choose one of the exiled cards and put it onto the battlefield under their control. Put the rest onto the battlefield under your control.

Coveted Jewel

When Coveted Jewel enters, draw three cards.
{T}: Add three mana of any one color.
Whenever one or more creatures an opponent controls attack you and aren't blocked, that player draws three cards and gains control of Coveted Jewel. Untap it.

Trostani Discordant

Other creatures you control get +1/+1.
When Trostani Discordant enters, create two 1/1 white Soldier creature tokens with lifelink.
At the beginning of your end step, each player gains control of all creatures they own.

Brooding Saurian

At the beginning of each end step, each player gains control of all nontoken permanents they own.

Homeward Path

{T}: Add {C}.
{T}: Each player gains control of all creatures they own.

Avarice Amulet

Equipped creature gets +2/+0 and has vigilance and "At the beginning of your upkeep, draw a card."
Whenever equipped creature dies, target opponent gains control of Avarice Amulet.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Loxodon Peacekeeper

At the beginning of your upkeep, the player with the lowest life total gains control of Loxodon Peacekeeper. If two or more players are tied for lowest life total, you choose one of them, and that player gains control of Loxodon Peacekeeper.

Contested War Zone

Whenever a creature deals combat damage to you, that creature's controller gains control of Contested War Zone.
{T}: Add {C}.
{1}, {T}: Attacking creatures get +1/+0 until end of turn.

Wild Mammoth

At the beginning of your upkeep, if a player controls more creatures than each other player, the player who controls the most creatures gains control of Wild Mammoth.