Malfunction

Enchant artifact or creature
When Malfunction enters, tap enchanted permanent.
Enchanted permanent doesn't untap during its controller's untap step.

Croaking Curse

Tap target creature. Create a Cursed Role token attached to it. (Enchanted creature is 1/1.)

Vantress Transmuter

Vantress Transmuter // Croaking Curse

Bladebrand

Target creature gains deathtouch until end of turn.
Draw a card.

Staunch Throneguard

Vigilance
When Staunch Throneguard enters, you become the monarch.

Swamp

Castaway's Despair

Enchant creature
When Castaway's Despair enters, tap enchanted creature.
Enchanted creature doesn't untap during its controller's untap step.

Spell Blast

Counter target spell with mana value X. (For example, if that spell's mana cost is {3}{U}{U}, X is 5.)

Feral Abomination

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)

Syphon Essence

Counter target creature or planeswalker spell. Create a Blood token. (It's an artifact with "{1}, {T}, Discard a card, Sacrifice this artifact: Draw a card.")

Paralyzing Grasp

Enchant creature
Enchanted creature doesn't untap during its controller's untap step.

Island

Dimir Guildmage

({U/B} can be paid with either {U} or {B}.)
{3}{U}: Target player draws a card. Activate only as a sorcery.
{3}{B}: Target player discards a card. Activate only as a sorcery.