Professor Onyx

copy a sorcery — 83 cards in the game can cause this.

1. Lithoform Engine — When an instant is copied thanks to Lithoform Engine, Professor Onyx makes each opponent lose 2 life
2. Mirrorpool — When an instant is copied thanks to Mirrorpool, Professor Onyx makes each opponent lose 2 life
3. Wondrous Crucible — When an instant is copied thanks to Wondrous Crucible, Professor Onyx makes each opponent lose 2 life
4. Panoptic Mirror — When an instant is copied thanks to Panoptic Mirror, Professor Onyx makes each opponent lose 2 life
5. Lucky Clover — When an Adventure is copied thanks to Lucky Clover, Professor Onyx makes each opponent lose 2 life
6. Twinning Staff — When Twinning Staff is copied, Professor Onyx makes each opponent lose 2 life

77 other cards cause it too. These are the ones with the most connections.

copy an instant — 87 cards in the game can cause this.

When an instant is copied thanks to:

1. Spellbinder — Professor Onyx makes each opponent lose 2 life
2. Isochron Scepter — Professor Onyx makes each opponent lose 2 life

85 other cards cause it too. These are the ones with the most connections.

a planeswalker it grants abilities to — 312 cards in the game can cause this.

1. Way of the Deathbringer — Way of the Deathbringer gives Professor Onyx an extra ability

311 other cards cause it too. These are the ones with the most connections.

a planeswalker is cast — 361 cards in the game can cause this (Professor Onyx is one).

When Professor Onyx is cast:

1. Jaya's Phoenix — returns itself from the graveyard
2. Interplanar Beacon — gains you 1 life
3. Defiler of Flesh — gives +1/+1
4. Primeval Bounty — puts 3 counters on a creature
5. Tetsuko Umezawa, Pursuer — gets +1/+1
6. Thor, God of Thunder — deals that spell's mana value damage
7. Krile Baldesion — brings a card back
8. Summon: Good King Mog XII — makes a token
9. Kykar, Wind's Fury — makes a token
10. Blood Funnel — sacrifices a creature

239 other cards care about it too. These are the ones with the most connections.

a planeswalker enters the battlefield — 366 cards in the game can cause this (Professor Onyx is one).

When Professor Onyx enters:

1. Builder's Talent — puts a counter on a creature
2. Brainstealer Dragon — makes a player lose life equal to its mana value
3. Cloudstone Curio — triggers

2 other cards care about it too. These are the ones with the most connections.

a nontoken creature is sacrificed — 1,714 cards in the game can cause this (Professor Onyx is one).

1. Fumulus, the Infestation — When a creature is sacrificed thanks to Professor Onyx, Fumulus, the Infestation makes a token

1 other card cares about it too. These are the ones with the most connections.

a creature is sacrificed — 1,741 cards in the game can cause this (Professor Onyx is one).

When a creature is sacrificed thanks to Professor Onyx:

1. Caesar, Legion's Emperor — makes 2 tokens
2. Malik, Grim Manipulator — makes a token
3. Thraximundar — puts a +1/+1 counter on itself
4. Legate Lanius, Caesar's Ace — puts a +1/+1 counter on itself
5. Zodiark, Umbral God — puts a +1/+1 counter on itself
6. Evin, Waterdeep Opportunist — makes a token
7. Mortician Beetle — puts a +1/+1 counter on itself

22 other cards care about it too. These are the ones with the most connections.

a card is discarded — 2,042 cards in the game can cause this (Professor Onyx is one).

When a permanent makes a player discard a card thanks to Professor Onyx:

1. Lo and Li, Royal Advisors — puts a counter on an Advisor
2. Sangromancer — gains you 3 life
3. Nath of the Gilt-Leaf — makes a token
4. Tourach, Dread Cantor — puts a +1/+1 counter on itself
5. Tinybones, Pocket Nuisance — deals 1 damage
6. Tinybones, Bauble Burglar — hits a graveyard
7. Fell Specter — makes each opponent lose 2 life
8. Spirit Cairn — makes a token
9. Confessor — gains you 1 life
10. Hostile Investigator — triggers

53 other cards care about it too. These are the ones with the most connections.

life is gained — 2,076 cards in the game can cause this (Professor Onyx is one).

When Professor Onyx gains life:

1. Titanbones, Towering Heart — puts 2 +1/+1 counters on itself
2. Dina, Soul Steeper — makes each opponent lose 1 life
3. Marina Vendrell's Grimoire — draws you that many cards
4. South Wind Avatar — makes each opponent lose 1 life
5. Rodolf Duskbringer — grants indestructible
6. Fiendish Panda — puts a +1/+1 counter on itself
7. Veinwitch Coven — brings a card back
8. Cleric Class — puts a counter on a creature
9. Lich's Mastery — draws you that many cards
10. Wall of Limbs — puts a +1/+1 counter on itself

84 other cards care about it too. These are the ones with the most connections.

a creature in a graveyard — 2,769 cards in the game can cause this (Professor Onyx is one).

Professor Onyx puts cards into the:

1. Chainer, Dementia Master — graveyard that Chainer, Dementia Master can bring back
2. Liliana the Repentant — graveyard that Liliana the Repentant can bring back
3. Grist, the Hunger Tide — graveyard, and Grist, the Hunger Tide gets bigger
4. Riveteers Ascendancy — graveyard that Riveteers Ascendancy can bring back
5. Edgar's Awakening — graveyard that Edgar's Awakening can bring back
6. Havengul Lich — graveyard that Havengul Lich can bring back
7. Paleoloth — graveyard that Paleoloth can bring back
8. Chainer, Nightmare Adept — graveyard that Chainer, Nightmare Adept can bring back
9. Banon, the Returners' Leader — graveyard that Banon, the Returners' Leader can bring back
10. Surgical Suite // Hospital Room — graveyard that Surgical Suite // Hospital Room can bring back

799 other cards care about it too. These are the ones with the most connections.

a nontoken creature dies — 2,769 cards in the game can cause this (Professor Onyx is one).

When a creature dies thanks to Professor Onyx:

1. Vraska, the Silencer — brings a card back
2. High-Society Hunter — draws you 1 card
3. Overseer of the Damned — makes a token
4. Shelob, Dread Weaver — hits a graveyard

66 other cards care about it too. These are the ones with the most connections.

life is lost — 3,160 cards in the game can cause this (Professor Onyx is one).

1. Zahur, Glory's Past — When a permanent makes a player lose life thanks to Professor Onyx, Zahur, Glory's Past raises your speed

55 other cards care about it too. These are the ones with the most connections.

cast a sorcery — 3,720 cards in the game can cause this.

1. Sword of Once and Future — When an instant is cast thanks to Sword of Once and Future, Professor Onyx makes each opponent lose 2 life
2. Glamdring — When an instant is cast thanks to Glamdring, Professor Onyx makes each opponent lose 2 life
3. Author of Shadows — When an instant is cast thanks to Author of Shadows, Professor Onyx makes each opponent lose 2 life
4. Treasure Keeper — When an instant is cast thanks to Treasure Keeper, Professor Onyx makes each opponent lose 2 life
5. Bismuth Mindrender — When an instant is cast thanks to Bismuth Mindrender, Professor Onyx makes each opponent lose 2 life
6. The Dawning Archaic — When an instant is cast thanks to The Dawning Archaic, Professor Onyx makes each opponent lose 2 life
7. Sarevok's Tome — When an instant is cast thanks to Sarevok's Tome, Professor Onyx makes each opponent lose 2 life
8. Brain in a Jar — When an instant is cast thanks to Brain in a Jar, Professor Onyx makes each opponent lose 2 life
9. Bösium Strip — When an instant is cast thanks to Bösium Strip, Professor Onyx makes each opponent lose 2 life
10. Sins of the Past — When Sins of the Past is cast, Professor Onyx makes each opponent lose 2 life

3,710 other cards cause it too. These are the ones with the most connections.

cast an instant — 3,931 cards in the game can cause this.

1. Ashnod's Intervention — When Ashnod's Intervention is cast, Professor Onyx makes each opponent lose 2 life
2. Feign Death — When Feign Death is cast, Professor Onyx makes each opponent lose 2 life
3. Undying Malice — When Undying Malice is cast, Professor Onyx makes each opponent lose 2 life
4. Vincent's Limit Break — When Vincent's Limit Break is cast, Professor Onyx makes each opponent lose 2 life
5. Demonic Gifts — When Demonic Gifts is cast, Professor Onyx makes each opponent lose 2 life
6. Empty the Pits — When Empty the Pits is cast, Professor Onyx makes each opponent lose 2 life
7. Nurgle's Conscription — When Nurgle's Conscription is cast, Professor Onyx makes each opponent lose 2 life
8. Zuko's Conviction — When Zuko's Conviction is cast, Professor Onyx makes each opponent lose 2 life
9. Misinformation — When Misinformation is cast, Professor Onyx makes each opponent lose 2 life
10. Shadow of the Grave — When Shadow of the Grave is cast, Professor Onyx makes each opponent lose 2 life

3,921 other cards cause it too. These are the ones with the most connections.

a card in a graveyard — 7,589 cards in the game can cause this (Professor Onyx is one).

1. Pitchstone Wall — Professor Onyx puts cards into the graveyard that Pitchstone Wall can bring back
2. Containment Construct — Professor Onyx puts cards into the graveyard that Containment Construct can bring back
3. Moonstone, Harsh Mistress — Professor Onyx puts cards into the graveyard that Moonstone, Harsh Mistress can bring back
4. Decaying Soil — Professor Onyx fills your graveyard toward the 7 or more cards Decaying Soil needs

440 other cards care about it too. These are the ones with the most connections.