Ertha Jo, Frontier Mentor

provide a creature to sacrifice — 2,720 cards in the game can cause this.

1. Industrial Advancement — Ertha Jo, Frontier Mentor makes fodder for Industrial Advancement
2. Divergent Transformations — Ertha Jo, Frontier Mentor makes fodder for Divergent Transformations
3. Transmogrify — Ertha Jo, Frontier Mentor makes fodder for Transmogrify

2,717 other cards cause it too. These are the ones with the most connections.

a creature token enters the battlefield — 2,799 cards in the game can cause this (Ertha Jo is one).

When a Mercenary enters thanks to Ertha Jo, Frontier Mentor:

1. Securitron Squadron — puts a counter on a permanent
2. Anointer Priest — gains you 1 life
3. Nesting Dovehawk — puts a +1/+1 counter on itself

a creature token is created — 2,799 cards in the game can cause this (Ertha Jo is one).

1. Staff of the Storyteller — When Ertha Jo, Frontier Mentor makes a Mercenary token, Staff of the Storyteller puts a story counter on itself

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

a token enters the battlefield — 3,710 cards in the game can cause this (Ertha Jo is one).

When a Mercenary enters thanks to Ertha Jo, Frontier Mentor:

1. Baron Bertram Graywater — makes a token
2. Marneus Calgar — draws you 1 card
3. Belladonna Took — gains you 1 life
4. Kambal, Profiteering Mayor — makes each opponent lose 1 life
5. Lucy MacLean, Positively Armed — makes a token
6. Mister Fantastic, Reed Richards — draws you 1 card
7. Cloakwood Swarmkeeper — puts a +1/+1 counter on itself
8. Woodland Champion — puts that many +1/+1 counters on itself
9. Leonardo, the Balance — puts a counter on a creature
10. Spiritcall Enthusiast // Scrollboost — becomes prepared

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

a token is created — 3,711 cards in the game can cause this (Ertha Jo is one).

When Ertha Jo, Frontier Mentor makes a Mercenary token:

1. Akim, the Soaring Wind — makes a token
2. Idol of Oblivion — draws you 1 card
3. Rosie Cotton of South Lane — puts a counter on a permanent
4. Mirkwood Bats — makes each opponent lose 1 life

17 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 (Ertha Jo is one).

When Ertha Jo, Frontier Mentor 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

122 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 (Ertha Jo is one).

When Ertha Jo, Frontier Mentor 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

194 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 (Ertha Jo is one).

When Ertha Jo, Frontier Mentor 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

20 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 (Ertha Jo is one).

When Ertha Jo, Frontier Mentor attacks:

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

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

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

331 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.

1. Prowl, Stoic Strategist // Prowl, Pursuit Vehicle — When a Mercenary enters thanks to Ertha Jo, Frontier Mentor, Prowl, Stoic Strategist // Prowl, Pursuit Vehicle puts a +1/+1 counter on itself
2. Aether Vial — When Ertha Jo, Frontier Mentor enters thanks to Aether Vial, it makes a token
3. Mercadian Lift — When Ertha Jo, Frontier Mentor enters thanks to Mercadian Lift, it makes a token
4. Belbe's Portal — When Ertha Jo, Frontier Mentor enters thanks to Belbe's Portal, it makes a token
5. Dragon Arch — When Ertha Jo, Frontier Mentor enters thanks to Dragon Arch, it makes a token
6. Quicksilver Amulet — When Ertha Jo, Frontier Mentor enters thanks to Quicksilver Amulet, it makes a token
7. Helvault — When Ertha Jo, Frontier Mentor enters thanks to Helvault, it makes a token
8. Tawnos's Coffin — When Ertha Jo, Frontier Mentor enters thanks to Tawnos's Coffin, it makes a token
9. Planar Bridge — When Ertha Jo, Frontier Mentor enters thanks to Planar Bridge, it makes a token
10. Thran Temporal Gateway — When Ertha Jo, Frontier Mentor enters thanks to Thran Temporal Gateway, it makes a token
11. Lantern of Revealing — When Ertha Jo, Frontier Mentor enters thanks to Lantern of Revealing, it makes a token

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