Sanctum Seeker

a Vampire attacks — 484 cards in the game can cause this.

1. Glass-Cast Heart — When Sanctum Seeker attacks, Glass-Cast Heart makes a token
2. Blood Seeker — When Blood Seeker attacks, Sanctum Seeker makes each opponent lose 1 life
3. Shadow Alley Denizen — When Shadow Alley Denizen attacks, Sanctum Seeker makes each opponent lose 1 life
4. Clandestine Meddler — When Clandestine Meddler attacks, Sanctum Seeker makes each opponent lose 1 life
5. Stensian Sanguinist // Exsanguinate — When Stensian Sanguinist // Exsanguinate attacks, Sanctum Seeker makes each opponent lose 1 life
6. Tenured Inkcaster — When Tenured Inkcaster attacks, Sanctum Seeker makes each opponent lose 1 life
7. Necropolis Regent — When Necropolis Regent attacks, Sanctum Seeker makes each opponent lose 1 life
8. Repentant Vampire — When Repentant Vampire attacks, Sanctum Seeker makes each opponent lose 1 life
9. Treacherous Vampire — When Treacherous Vampire attacks, Sanctum Seeker makes each opponent lose 1 life
10. The Haunt of Hightower — When The Haunt of Hightower attacks, Sanctum Seeker makes each opponent lose 1 life
11. Krovikan Vampire — When Krovikan Vampire attacks, Sanctum Seeker makes each opponent lose 1 life

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

a nontoken Vampire attacks — 484 cards in the game can cause this (Sanctum Seeker is one).

1. Mavren Fein, Dusk Apostle — When Sanctum Seeker attacks, Mavren Fein, Dusk Apostle makes a token

a Vampire creature is cast — 484 cards in the game can cause this (Sanctum Seeker is one).

1. Bloodlord of Vaasgoth — When Sanctum Seeker is cast, Bloodlord of Vaasgoth grants bloodthirst

a Vampire deals combat damage — 484 cards in the game can cause this (Sanctum Seeker is one).

When Sanctum Seeker deals combat damage:

1. Rakish Heir — puts a counter on a permanent
2. Stensia Masquerade — puts a counter on a permanent

a Vampire enters the battlefield — 500 cards in the game can cause this (Sanctum Seeker is one).

When Sanctum Seeker enters:

1. Anje, Maid of Dishonor — makes a token
2. Forerunner of the Legion — gives +1/+1
3. Markov Enforcer — deals damage
4. Evelyn, the Covetous — exiles a card from a library

a Knight attacks — 547 cards in the game can cause this (Sanctum Seeker is one).

1. Knights' Charge — When Sanctum Seeker attacks, Knights' Charge makes each opponent lose 1 life

a Knight deals combat damage — 547 cards in the game can cause this (Sanctum Seeker is one).

1. Exsanguinator Cavalry — When Sanctum Seeker deals combat damage, Exsanguinator Cavalry puts a counter on a permanent

a Knight enters the battlefield — 592 cards in the game can cause this (Sanctum Seeker is one).

When Sanctum Seeker enters:

1. Brimstone Trebuchet — untaps itself
2. Zhalfirin Lancer — gets +1/+1

a Knight creature it grants types to — 596 cards in the game can cause this.

1. Dark Knight's Greatsword — Dark Knight's Greatsword gives Sanctum Seeker an extra creature type

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

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

When Sanctum Seeker gains life:

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

84 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 (Sanctum Seeker is one).

When a permanent makes a player lose life thanks to Sanctum Seeker:

1. Far Fortune, End Boss — raises your speed
2. Zahur, Glory's Past — raises your speed
3. Mendicant Core, Guidelight — raises your speed
4. Aether Syphon — raises your speed
5. Vnwxt, Verbose Host — raises your speed
6. Embalmed Ascendant — raises your speed
7. Slick Imitator — raises your speed
8. Nesting Bot — raises your speed
9. Howlsquad Heavy — raises your speed
10. Hour of Victory — raises your speed

46 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 (Sanctum Seeker is one).

When Sanctum Seeker attacks:

1. Temmet, Naktamun's Will — draws you 1 card
2. Grim Javelineer — gives +1/+0
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
9. Toph, Earthbending Master — puts a counter on a permanent
10. Three Dog, Galaxy News DJ — sacrifices an Aura

116 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 (Sanctum Seeker is one).

When Sanctum Seeker attacks:

1. Adaptive Omnitool — searches a library
2. Anthem of Rakdos — gives +2/+0
3. Kindred Discovery — draws you 1 card
4. Invasion of New Capenna // Holy Frazzle-Cannon — puts counters on a permanent
5. Chorale of the Void — brings a card back
6. Saw — sacrifices a creature
7. Gisa's Favorite Shovel — makes an opponent sacrifice a creature
8. Ultima Weapon — kills a creature an opponent controls

183 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 (Sanctum Seeker is one).

When Sanctum Seeker blocks:

1. Tide of War — sacrifices a creature
2. Dead-Iron Sledge — kills a creature

26 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 (Sanctum Seeker is one).

When Sanctum Seeker 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

311 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 (Sanctum Seeker is one).

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

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