Circle of Affliction

As Circle of Affliction enters, choose a color.
Whenever a source of the chosen color deals damage to you, you may pay {1}. If you do, target player loses 1 life and you gain 1 life.

Circle of Elders

Vigilance
Formidable — {T}: Add {C}{C}{C}. Activate only if creatures you control have total power 8 or greater.

Sphere of Law

If a red source would deal damage to you, prevent 2 of that damage.

Sphere of Safety

Creatures can't attack you or planeswalkers you control unless their controller pays {X} for each of those creatures, where X is the number of enchantments you control.

Circle of the Moon Druid

Bear Form — During your turn, Circle of the Moon Druid is a Bear with base power and toughness 4/2. (It loses all other creature types.)

Lavaball Trap

If an opponent had two or more lands enter the battlefield under their control this turn, you may pay {3}{R}{R} rather than pay this spell's mana cost.
Destroy two target lands. Lavaball Trap deals 4 damage to each creature.

Circle of Flame

Whenever a creature without flying attacks you or a planeswalker you control, Circle of Flame deals 1 damage to that creature.

Crystal Ball

{1}, {T}: Scry 2. (Look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Verity Circle

Whenever a creature an opponent controls becomes tapped, if it isn't being declared as an attacker, you may draw a card.
{4}{U}: Tap target creature without flying.

Sphere of Reason

If a blue source would deal damage to you, prevent 2 of that damage.

Detention Sphere

When Detention Sphere enters, you may exile target nonland permanent not named Detention Sphere and all other permanents with the same name as that permanent.
When Detention Sphere leaves the battlefield, return the exiled cards to the battlefield under their owner's control.

Wrecking Ball

Orb of Dreams

Farideh's Fireball

Farideh's Fireball deals 5 damage to target creature or planeswalker. Roll a d20.
1—9 | Farideh's Fireball deals 2 damage to each player.
10—20 | Farideh's Fireball deals 2 damage to each opponent.

Orbweaver Kumo

Reach (This creature can block creatures with flying.)
Whenever you cast a Spirit or Arcane spell, Orbweaver Kumo gains forestwalk until end of turn. (It can't be blocked as long as defending player controls a Forest.)

Sphere of Grace

If a black source would deal damage to you, prevent 2 of that damage.

Teleportation Circle

At the beginning of your end step, exile up to one target artifact or creature you control, then return that card to the battlefield under its owner's control.

Wastes

Sphere of Annihilation

Sphere of Annihilation enters with X void counters on it.
At the beginning of your upkeep, exile Sphere of Annihilation, all creatures and planeswalkers with mana value less than or equal to the number of void counters on it, and all creature and planeswalker cards in graveyards with mana value less than or equal to the number of void counters on it.

Balloon Peddler

{U}, {T}, Discard a card: Target creature gains flying until end of turn.

Sphere of Purity

If an artifact would deal damage to you, prevent 1 of that damage.

Jar of Eyeballs

Whenever a creature you control dies, put two eyeball counters on Jar of Eyeballs.
{3}, {T}, Remove all eyeball counters from Jar of Eyeballs: Look at the top X cards of your library, where X is the number of eyeball counters removed this way. Put one of them into your hand and the rest on the bottom of your library in any order.

Orbs of Warding

You have hexproof. (You can't be the target of spells or abilities your opponents control.)
If a creature would deal damage to you, prevent 1 of that damage.

Static Orb

As long as Static Orb is untapped, players can't untap more than two permanents during their untap steps.

Circle of Protection: Artifacts

{2}: The next time an artifact source of your choice would deal damage to you this turn, prevent that damage.

Winter Orb

As long as Winter Orb is untapped, players can't untap more than one land during their untap steps.

Story Circle

As Story Circle enters, choose a color.
{W}: The next time a source of your choice of the chosen color would deal damage to you this turn, prevent that damage.

Capture Sphere

Flash (You may cast this spell any time you could cast an instant.)
Enchant creature
When Capture Sphere enters, tap enchanted creature.
Enchanted creature doesn't untap during its controller's untap step.

Sphere of Duty

If a green source would deal damage to you, prevent 2 of that damage.

Circle of Protection: White

{1}: The next time a white source of your choice would deal damage to you this turn, prevent that damage.

Protective Sphere

{1}, Pay 1 life: Prevent all damage that would be dealt to you this turn by a source of your choice that shares a color with the mana spent on this activation cost. (Colorless mana prevents no damage.)

Circle of Despair

{1}, Sacrifice a creature: The next time a source of your choice would deal damage to any target this turn, prevent that damage.

Circle of Protection: Blue

{1}: The next time a blue source of your choice would deal damage to you this turn, prevent that damage.

Watcher of the Spheres

Flying
Creature spells with flying you cast cost {1} less to cast.
Whenever another creature you control with flying enters, Watcher of the Spheres gets +1/+1 until end of turn.

Phantasmal Sphere

Flying
At the beginning of your upkeep, put a +1/+1 counter on Phantasmal Sphere, then sacrifice Phantasmal Sphere unless you pay {1} for each +1/+1 counter on it.
When Phantasmal Sphere leaves the battlefield, target opponent creates an X/X blue Orb creature token with flying, where X is the number of +1/+1 counters on Phantasmal Sphere.

The Circle of Loyalty

This spell costs {1} less to cast for each Knight you control.
Creatures you control get +1/+1.
Whenever you cast a legendary spell, create a 2/2 white Knight creature token with vigilance.
{3}{W}, {T}: Create a 2/2 white Knight creature token with vigilance.

Zuran Orb

Fireball

This spell costs {1} more to cast for each target beyond the first.
Fireball deals X damage divided evenly, rounded down, among any number of targets.

Ball Lightning

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
Haste (This creature can attack and {T} as soon as it comes under your control.)
At the beginning of the end step, sacrifice this creature.

Circle of Solace

As Circle of Solace enters, choose a creature type.
{1}{W}: The next time a creature of the chosen type would deal damage to you this turn, prevent that damage.

Gravity Sphere

Circle of Protection: Black

{1}: The next time a black source of your choice would deal damage to you this turn, prevent that damage.

Circle of Confinement

When Circle of Confinement enters, exile target creature an opponent controls with mana value 3 or less until Circle of Confinement leaves the battlefield.
Whenever an opponent casts a Vampire spell with the same name as a card exiled with Circle of Confinement, you gain 2 life.

Rhystic Circle

{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.

Mindlock Orb

Mesmeric Orb

Whenever a permanent becomes untapped, that permanent's controller mills a card.

Prismatic Circle

Cumulative upkeep {1} (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)
As Prismatic Circle enters, choose a color.
{1}: The next time a source of your choice of the chosen color would deal damage to you this turn, prevent that damage.

Sphere of Truth

If a white source would deal damage to you, prevent 2 of that damage.

Circle of Dreams Druid

{T}: Add {G} for each creature you control.

Circle of Protection: Green

{1}: The next time a green source of your choice would deal damage to you this turn, prevent that damage.

Circle of Protection: Red

{1}: The next time a red source of your choice would deal damage to you this turn, prevent that damage.

Torpor Orb

Creatures entering don't cause abilities to trigger.

Strixhaven Stadium

{T}: Add {C}. Put a point counter on Strixhaven Stadium.
Whenever a creature deals combat damage to you, remove a point counter from Strixhaven Stadium.
Whenever a creature you control deals combat damage to an opponent, put a point counter on Strixhaven Stadium. Then if it has ten or more point counters on it, remove them all and that player loses the game.