Wall of Junk

an artifact attacks — 1,243 cards in the game can cause this (Wall of Junk is one).

When Wall of Junk attacks:

1. Alibou, Ancient Witness — deals X damage
2. Bio-Asset Allocator — makes each opponent lose 1 life
3. Assaultron Dominator — puts a counter on a permanent
4. Aloy, Savior of Meridian — triggers

an artifact deals combat damage — 1,243 cards in the game can cause this (Wall of Junk is one).

When Wall of Junk deals combat damage:

1. Locutus of Borg — makes a token
2. Sharding Sphinx — makes a token
3. Antagonist Incorporator — makes a token
4. Research Thief — draws you 1 card
5. Thopter Spy Network — draws you 1 card
6. Hive Mind Coprocessor — makes you lose life
7. Pia Nalaar, Chief Mechanic — puts a counter on a permanent you control
8. Automated Assembly Line — triggers

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

a nontoken artifact deals combat damage — 1,243 cards in the game can cause this (Wall of Junk is one).

1. Virulent Silencer — When Wall of Junk deals combat damage, Virulent Silencer puts 2 counters on a permanent

an artifact leaves the battlefield — 1,680 cards in the game can cause this (Wall of Junk is one).

1. Sludge Strider — When Wall of Junk leaves the battlefield, Sludge Strider makes a player lose 1 life

an artifact is cast — 3,683 cards in the game can cause this (Wall of Junk is one).

When Wall of Junk is cast:

1. Mendicant Core, Guidelight — copies a spell
2. Sai, Master Thopterist — makes a token
3. Ravenous Robots — makes a token
4. Pinnacle Emissary — makes a token
5. Mirrodin Besieged — makes a token
6. Poetic Ingenuity — makes a token
7. Digsite Engineer — makes a token
8. Myrsmith — makes a token
9. Riddlesmith — draws you 1 card
10. Dr. Madison Li — puts a counter on a permanent you control

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

a nontoken artifact enters the battlefield — 3,768 cards in the game can cause this (Wall of Junk is one).

When Wall of Junk enters:

1. Ultron, Artificial Malevolence — makes a token
2. The Prydwen, Steel Flagship — makes a token
3. Conquest Mission — puts a quest counter on itself
4. Surge Conductor — proliferates
5. Replication Specialist — makes a token
6. Weapons Manufacturing — makes a token
7. Mirrorworks — makes a token

a nontoken creature leaves the battlefield — 4,133 cards in the game can cause this (Wall of Junk is one).

When Wall of Junk leaves the battlefield:

1. Tokka & Rahzar, Unsupervised — puts a +1/+1 counter on itself
2. Splinter, the Mentor — makes a token
3. Rat King, Pale Piper — makes a token
4. Dual Nature — exiles a creature

a creature leaves the battlefield — 4,238 cards in the game can cause this (Wall of Junk is one).

When Wall of Junk leaves the battlefield:

1. Lunarch Veteran // Luminous Phantom — gains you 1 life
2. Extractor Demon — mills a card
3. Aang, Airbending Master — puts a counter on a permanent
4. Dour Port-Mage — draws you 1 card
5. Vela the Night-Clad — makes each opponent lose 1 life
6. Taeko, the Patient Avalanche — scries
7. Ninth Bridge Patrol — puts a +1/+1 counter on itself
8. Funeral March — makes a player sacrifice a creature
9. Sally Sparrow — triggers
10. Aang, at the Crossroads // Aang, Destined Savior — triggers

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

an artifact enters the battlefield — 4,643 cards in the game can cause this (Wall of Junk is one).

When Wall of Junk enters:

1. Transplant Theorist — draws you 1 card
2. Elvish Archivist — puts 2 +1/+1 counters on itself
3. Golbez, Crystal Collector — surveils
4. Underhanded Designs — makes each opponent lose 1 life
5. Mechan Assembler — makes a token
6. Glassdust Hulk — gets +1/+1
7. Rook Turret — draws you 1 card
8. Hedron Detonator — deals 1 damage
9. Pactdoll Terror — makes each opponent lose 1 life
10. Mandible Justiciar — gets +1/+1

56 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 (Wall of Junk is one).

When Wall of Junk attacks:

1. Shaun, Father of Synths — makes a token
2. Invisible Woman — triggers

136 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 (Wall of Junk is one).

When Wall of Junk is cast:

1. Primeval Bounty — makes a token
2. Champions of the Perfect — draws you 1 card

89 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 (Wall of Junk is one).

1. Pollywog Prodigy — When Wall of Junk enters, Pollywog Prodigy puts a counter on itself

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