Enchanted creature can't be blocked unless defending player pays {3} for each creature they control that's blocking it.
{2}{U}{R}
Essence Backlash
Instant
Counter target creature spell. Essence Backlash deals damage equal to that spell's power to its controller.
{2}{R}
Insolence
Enchantment - Aura
Enchant creature
Whenever enchanted creature becomes tapped, Insolence deals 2 damage to that creature's controller.
{U}
Mana Chains
Enchantment - Aura
Enchant creature
Enchanted creature has "Cumulative upkeep {1}." (At the beginning of its controller's upkeep, that player puts an age counter on it, then sacrifices it unless they pay its upkeep cost for each age counter on it.)
{2}{U}{U}
Merseine
Enchantment - Aura
Enchant creature
Merseine enters the battlefield with three net counters on it.
Enchanted creature doesn't untap during its controller's untap step if Merseine has a net counter on it.
Pay enchanted creature's mana cost: Remove a net counter from Merseine. Only the controller of the enchanted creature may activate this ability.
{1}{U}
Pendrell Flux
Enchantment - Aura
Enchant creature
Enchanted creature has "At the beginning of your upkeep, sacrifice this creature unless you pay its mana cost."
{1}{U}
Power Taint
Enchantment - Aura
Enchant enchantment
At the beginning of the upkeep of enchanted enchantment's controller, that player loses 2 life unless they pay {2}.
Cycling {2} ({2}, Discard this card: Draw a card.)
{2}{R}
Raid Bombardment
Enchantment
Whenever a creature you control with power 2 or less attacks, Raid Bombardment deals 1 damage to the player or planeswalker that creature is attacking.
{2}{W}{W}
Rhystic Circle
Enchantment
{1}: Any player may pay {1}. If no one does, the next time a source of your choice would deal damage to you this turn, prevent that damage.
{2}{U}
Slow Motion
Enchantment - Aura
Enchant creature
At the beginning of the upkeep of enchanted creature's controller, that player sacrifices that creature unless they pay {2}.
When Slow Motion is put into a graveyard from the battlefield, return Slow Motion to its owner's hand.
{2}{U}
Soul Barrier
Enchantment
Whenever an opponent casts a creature spell, Soul Barrier deals 2 damage to that player unless they pay {2}.
{2}{W}{U}
Stormcaller's Boon
Enchantment
Sacrifice Stormcaller's Boon: Creatures you control gain flying until end of turn.
Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom of your library in a random order.)
{U}{U}
Sunken City
Enchantment
At the beginning of your upkeep, sacrifice Sunken City unless you pay {U}{U}.
Blue creatures get +1/+1.
{1}{U}
Teferi's Curse
Enchantment - Aura
Enchant artifact or creature
Enchanted permanent has phasing. (It phases in or out before its controller untaps during each of their untap steps. While it's phased out, it's treated as though it doesn't exist.)
{1}{U}
Volrath's Curse
Enchantment - Aura
Enchant creature
Enchanted creature can't attack or block, and its activated abilities can't be activated. That creature's controller may sacrifice a permanent for that player to ignore this effect until end of turn.
{1}{U}: Return Volrath's Curse to its owner's hand.
{U}
Awesome Presence
Enchantment - Aura
Enchant creature
Enchanted creature can't be blocked unless defending player pays {3} for each creature they control that's blocking it.
{U}
Awesome Presence
Enchantment - Aura
Enchant creature
Enchanted creature can't be blocked unless defending player pays {3} for each creature they control that's blocking it.
{U}
Awesome Presence
Enchantment - Aura
Enchant creature
Enchanted creature can't be blocked unless defending player pays {3} for each creature they control that's blocking it.
{2}{U}
Soul Barrier
Enchantment
Whenever an opponent casts a creature spell, Soul Barrier deals 2 damage to that player unless they pay {2}.
{2}{U}
Soul Barrier
Enchantment
Whenever an opponent casts a creature spell, Soul Barrier deals 2 damage to that player unless they pay {2}.
{2}{U}
Soul Barrier
Enchantment
Whenever an opponent casts a creature spell, Soul Barrier deals 2 damage to that player unless they pay {2}.