Undulating Witness

a creature is discarded — 206 cards in the game can cause this (Undulating Witness is one).

When Undulating Witness makes a player discard a card:

1. Wharf Infiltrator — makes a token
2. Bone Miser — makes a token
3. Hashaton, Scarab's Fist — makes a token
4. Surly Badgersaur — puts a +1/+1 counter on itself
5. Oskar, Rubbish Reclaimer — brings a card back
6. Conspiracy Theorist — brings a card back
7. Veronica, Dissident Scribe — makes a token
8. Green Goblin, Nemesis — puts a counter on a Goblin

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

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

When Undulating Witness makes a player discard a card:

1. Ivora, Insatiable Heir — puts a +1/+1 counter on itself
2. Cool but Rude — deals 2 damage
3. Containment Construct — brings a card back
4. Moonstone, Harsh Mistress — brings a card back
5. Lazotep Chancellor — puts 2 counters on a Zombie or Army
6. Magmakin Artillerist — deals that much damage
7. Inti, Seneschal of the Sun — exiles a card from your library
8. Pitchstone Wall — sacrifices itself
9. Currency Converter — exiles it
10. Hostile Investigator — triggers

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

a creature goes to a graveyard — 3,011 cards in the game can cause this (Undulating Witness is one).

When Undulating Witness hits the graveyard:

1. Syr Konrad, the Grim — deals 1 damage
2. Robot Domination — draws you 1 card
3. Voracious Brood — puts that many +1/+1 counters on itself
4. Dennick, Pious Apprentice // Dennick, Pious Apparition — triggers
5. Soulcipher Board // Cipherbound Spirit — triggers
6. Sefris of the Hidden Ways — triggers

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

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

1. Gale, Waterdeep Prodigy — When Undulating Witness is in the graveyard, Gale, Waterdeep Prodigy can bring it back
2. Transplant Theorist — When Undulating Witness is in the graveyard, Transplant Theorist can bring it back
3. Heart-Shaped Herb — When Undulating Witness is in the graveyard, Heart-Shaped Herb can bring it back
4. Wayward Angel — Undulating Witness fills your graveyard toward the 7 or more cards Wayward Angel needs
5. Rescue from the Underworld — When Undulating Witness is in the graveyard, Rescue from the Underworld can bring it back
6. Victimize — When Undulating Witness is in the graveyard, Victimize can bring it back
7. Bound // Determined — When Undulating Witness is in the graveyard, Bound // Determined can bring it back
8. Enlightened Confidant — When Undulating Witness is in the graveyard, Enlightened Confidant can bring it back
9. Tergrid, God of Fright // Tergrid's Lantern — When Undulating Witness is in the graveyard, Tergrid, God of Fright // Tergrid's Lantern can bring it back
10. Aerith, Last Ancient — When Undulating Witness is in the graveyard, Aerith, Last Ancient can bring it back

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

anything goes to a graveyard — 7,589 cards in the game can cause this (Undulating Witness is one).

When Undulating Witness hits the graveyard:

1. Quest for Ancient Secrets — puts a quest counter on itself
2. Planar Void — hits a graveyard
3. Measure of Wickedness — gives an opponent control of itself
4. Energy Field — sacrifices itself

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

anything attacks — 17,934 cards in the game can cause this (Undulating Witness is one).

When Undulating Witness attacks:

1. Far Fortune, End Boss — deals 1 damage
2. Temmet, Naktamun's Will — draws you 1 card
3. Invisible Woman — triggers
4. Caesar, Legion's Emperor — sacrifices a creature
5. Guide of Souls — triggers
6. Campsite Cuisine — sacrifices a Food
7. Gossip's Talent — triggers
8. Banon, the Returners' Leader — draws and discards

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

a creature attacks — 17,934 cards in the game can cause this (Undulating Witness is one).

When Undulating Witness attacks:

1. Adaptive Omnitool — searches a library
2. Anthem of Rakdos — gives +2/+0
3. Kindred Discovery — draws you 1 card
4. Saw — sacrifices a creature

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

a creature blocks — 17,934 cards in the game can cause this (Undulating Witness is one).

1. Tide of War — When Undulating Witness blocks, Tide of War sacrifices a creature

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

a creature is cast — 18,010 cards in the game can cause this (Undulating Witness is one).

1. Bloodbond March — When Undulating Witness is cast, Bloodbond March brings a card back

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

a nontoken creature enters the battlefield — 18,448 cards in the game can cause this (Undulating Witness is one).

1. Samwise Gamgee — When Undulating Witness enters, Samwise Gamgee makes a token

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

a creature enters the battlefield — 19,800 cards in the game can cause this (Undulating Witness is one).

When Undulating Witness enters:

1. Slash, Reptile Rampager — deals 2 damage
2. Ray Fillet, Wave Warrior — puts a counter on itself
3. The Neutrinos — gets +1/+0
4. Wingnut, Bat on the Belfry — grants flying, haste and menace
5. Aetherstorm Roc — puts a counter on a permanent you control
6. Raphael, Most Attitude — exiles a card from your library

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

anything enters the battlefield — 26,499 cards in the game can cause this (Undulating Witness is one).

1. Prowl, Stoic Strategist // Prowl, Pursuit Vehicle — When Undulating Witness enters, Prowl, Stoic Strategist // Prowl, Pursuit Vehicle puts a +1/+1 counter on itself

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