Are these custom MTG cards balanced for Modern and Commander?

[SeekerOfTruth007]

Petrified Ectoplasm U

Creature - Wall - Rare

Defender. (Walls can't attack.)

U: Petrified Ectoplasm gains Flying until end of turn.

U: Petrified Ectoplasm gains Hexproof until end of turn.

U: Untap Petrified Ectoplasm.

1: Petrified Ectoplasm gains +1/-1 until end of turn.

0/5

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The above creature is a Wall, so that's a drawback, and it's very much a mana hog, so it wastes most of your turn to use its abilities every turn.

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Final Count 4BBB

Legendary Creature - Vampire - Rare

Flying. Echo.

Rebirth. (You may Cast Final Count from your Graveyard. If you do, it Enters the Battlefield with a Finality Counter on it.)

When Final Count Enters the Battlefield, destroy target creature.

5/5

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Channel Beast 4GG

Creature - Beast - Rare

As you announce Channel Beast, you may pay up to 4 life. Channel Beast costs 1 less to cast for each 1 life paid this way.

6/6

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Xyxyl's Thrall 2B

Creature - Thrall - Rare

Sacrifice Xyxyl's Thrall: Add RBU to your mana pool.

2/2

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Rydia's Mother, Summoner of Mist BGU

Legendary Creature - Wizard - Rare

When you cast a spell, Manifest the top card of your Library.

3/3

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Now for some non-creature cards.

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Vampiric Feast XRBU

Sorcery - Rare

Spend only Red, Black, or Blue mana to cast Vampiric Feast.

Vampiric Feast deals X damage to target creature or player. You gain X Life.

Draw X cards.

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Cyan's Dream XGWU

Sorcery - Rare

Manifest the top X cards of your Library.

[AI Opinion]

Love this kind of homebrew stuff 😄 Let me go one by one.

Petrified Ectoplasm: Way undercosted. A 1-mana 0/5 with three cheap blue activations plus pump is a nightmare in Modern. Needs higher base cost (2U or 1UU), maybe lose one of hexproof/untap, or drop toughness.

Final Count: 4BBB 5/5 flying, ETB destroy a creature, then repeatable via graveyard is pushed. Echo barely matters here. Rebirth should probably exile it if it dies with a finality counter or cost more (like 6BB) or lose flying.

Channel Beast: Essentially a 2-mana 6/6 if you pay 4 life. That’s broken in Modern. Even 3 mana 6/6 with no drawback is too much. Either cap life payment at 2 or make it “for every 2 life you pay, it costs 1 less” and start at 5GG.

Xyxyl’s Thrall: At 2 mana for a 2/2 that sacs for RBU, this is extremely strong fast mana in Modern. Compare to Lotus Cobra or Dark Ritual. Probably needs to be 1/1, cost 3, or enter tapped/with summoning sickness restriction like “activate only as a sorcery.”

Rydia’s Mother: “When you cast a spell, manifest the top card” is insanely snowbally card advantage and board presence, especially in Commander. Needs “once each turn” or “noncreature spell” and probably to cost 4–5 mana.

Vampiric Feast: X damage, X life, and draw X at instant-speed-like sorcery rate in Grixis is far above Fireball + Sphinx’s Revelation territory. Needs to be “target creature OR planeswalker,” probably lose the card draw or the lifegain, or be XBBR and draw half X rounded down.

Cyan’s Dream: Manifesting X at 3 colors is powerful but probably fine if cost is X3GWU or sorcery speed with some cap. As written at XGWU it’s very pushed for Commander token/value decks but not immediately broken.

Overall, super creative flavor, but these would dominate Modern and many Commander tables without significant cost or text tweaks 🧠🎨