Relic Bane

Enchant artifact
Enchanted artifact has "At the beginning of your upkeep, you lose 2 life."

Relic Ward

You may cast Relic Ward as though it had flash. If you cast it any time a sorcery couldn't have been cast, the controller of the permanent it becomes sacrifices it at the beginning of the next cleanup step.
Enchant artifact
Enchanted artifact has shroud. (It can't be the target of spells or abilities.)

Warp Artifact

Enchant artifact
At the beginning of the upkeep of enchanted artifact's controller, Warp Artifact deals 1 damage to that player.

Crown of Doom

Whenever a creature attacks you or a planeswalker you control, it gets +2/+0 until end of turn.
{2}: Target player other than Crown of Doom's owner gains control of it. Activate only during your turn.

Eriette of the Charmed Apple

Each creature that's enchanted by an Aura you control can't attack you or planeswalkers you control.
At the beginning of your end step, each opponent loses X life and you gain X life, where X is the number of Auras you control.

Artifact Possession

Enchant artifact
Whenever enchanted artifact becomes tapped or a player activates an ability of enchanted artifact without {T} in its activation cost, Artifact Possession deals 2 damage to that artifact's controller.

Ghoulish Impetus

Enchant creature
Enchanted creature gets +1/+1, has deathtouch, and is goaded.
When enchanted creature dies, return Ghoulish Impetus to the battlefield at the beginning of the next end step.

Overencumbered

Enchant opponent
When Overencumbered enters, enchanted opponent creates a Clue token, a Food token, and a Junk token.
At the beginning of combat on enchanted opponent's turn, that player may pay {1} for each artifact they control. If they don't, creatures can't attack this combat.

Jinxed Choker

At the beginning of your end step, target opponent gains control of Jinxed Choker and puts a charge counter on it.
At the beginning of your upkeep, Jinxed Choker deals damage to you equal to the number of charge counters on it.
{3}: Put a charge counter on Jinxed Choker or remove one from it.