Archelos, Lagoon Mystic

anything untaps — 1 card in the game can cause this (Archelos is one).

1. Tui and La, Moon and Ocean — When Tui and La, Moon and Ocean untaps thanks to Archelos, Lagoon Mystic, it puts a counter on a permanent
2. Merieke Ri Berit — When Merieke Ri Berit untaps thanks to Archelos, Lagoon Mystic, it kills a creature
3. King Macar, the Gold-Cursed — When King Macar, the Gold-Cursed untaps thanks to Archelos, Lagoon Mystic, it exiles a creature an opponent controls
4. The Pandorica — When The Pandorica untaps thanks to Archelos, Lagoon Mystic, it triggers

a permanent untaps — 66 cards in the game can cause this (Archelos is one).

When a permanent untaps thanks to Archelos, Lagoon Mystic:

1. Mesmeric Orb — mills a card
2. Wake Thrasher — gets +1/+1

a Turtle it boosts — 154 cards in the game can cause this.

1. Turtle Power! — Turtle Power! gives Archelos, Lagoon Mystic bigger stats

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

a Shaman creature enters the battlefield — 539 cards in the game can cause this (Archelos is one).

1. Thornbite Staff — When Archelos, Lagoon Mystic enters, Thornbite Staff triggers

an artifact it applies untap to — 4,531 cards in the game can cause this (Archelos is one).

1. Storm the Vault // Vault of Catlacan — Archelos, Lagoon Mystic gives Storm the Vault // Vault of Catlacan an extra untap

4,530 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 (Archelos is one).

When Archelos, Lagoon Mystic attacks:

1. Far Fortune, End Boss — deals 1 damage
2. Temmet, Naktamun's Will — draws you 1 card
3. Grim Javelineer — gives +1/+0
4. Invisible Woman — triggers
5. Caesar, Legion's Emperor — sacrifices a creature
6. Guide of Souls — triggers
7. Campsite Cuisine — sacrifices a Food
8. Gossip's Talent — triggers
9. Banon, the Returners' Leader — draws and discards
10. Toph, Earthbending Master — puts a counter on a permanent

496 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 (Archelos is one).

When Archelos, Lagoon Mystic 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. Anim Pakal, Thousandth Moon — puts a +1/+1 counter on itself
7. Saw — sacrifices a creature
8. Gisa's Favorite Shovel — makes an opponent sacrifice a creature
9. Ultima Weapon — kills a creature an opponent controls
10. Total War — kills a creature

873 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 (Archelos is one).

When Archelos, Lagoon Mystic blocks:

1. Mage Hunters' Onslaught — makes a player lose 1 life
2. Carnage Gladiator — makes a player lose 1 life
3. Barrow-Blade — strips abilities
4. Heat of Battle — deals 1 damage
5. Battle Strain — deals 1 damage
6. Favor of the Woods — gains you 3 life
7. Tide of War — sacrifices a creature
8. Dead-Iron Sledge — kills a creature
9. Dwindle — kills a creature
10. Shield of the Righteous — triggers

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

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

When Archelos, Lagoon Mystic attacks:

1. Mardu Ascendancy — makes a token
2. Basri Ket — makes a token
3. Militia's Pride — makes a token

a creature it applies untap to — 19,392 cards in the game can cause this (Archelos is one).

Archelos, Lagoon Mystic gives:

1. Extravagant Replication — an extra untap
2. Urza's Saga — an extra untap
3. Staff of Titania — an extra untap
4. The Rani — an extra untap
5. Dowsing Dagger // Lost Vale — an extra untap
6. Thopter Spy Network — an extra untap
7. Dovin, Grand Arbiter — an extra untap
8. Kaito, Dancing Shadow — an extra untap
9. Saheeli, Sublime Artificer — an extra untap
10. Metallurgic Summonings — an extra untap

19,381 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 (Archelos is one).

When Archelos, Lagoon Mystic enters:

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

3,029 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 (Archelos is one).

1. Prowl, Stoic Strategist // Prowl, Pursuit Vehicle — When Archelos, Lagoon Mystic enters, Prowl, Stoic Strategist // Prowl, Pursuit Vehicle puts a +1/+1 counter on itself

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