Agatha's Soul Cauldron + Walking Ballista + Butcher Ghoul

Agatha's Soul Cauldron
Walking Ballista
Butcher Ghoul

Requires
Agatha's Soul Cauldron must be on the battlefield. Walking Ballista must be in exile (exiled by Agatha's Soul Cauldron). Butcher Ghoul must be on the battlefield. Butcher Ghoul has at least one +1/+1 counter on it.
Steps
  1. Activate Butcher Ghoul using Walking Ballista's second ability by removing a +1/+1 counter from it.
  2. Repeat step 1 until Butcher Ghoul has no +1/+1 counters on it.
  3. Resolve all Butcher Ghoul abilities dealing 1 damage to Butcher Ghoul, and any remaining damage to any target(s).
  4. Butcher Ghoul dies as a state-based action due to having 0 toughness.
  5. Butcher Ghoul's undying ability triggers, returning it from your graveyard to the battlefield with a +1/+1 counter on it.
  6. Repeat.
Results
Infinite death triggers. Infinite ETB. Infinite LTB.

Yawgmoth, Thran Physician
0.25% of 5611 decks 14 decks
Tayam, Luminous Enigma
0.12% of 5866 decks 7 decks
Hapatra, Vizier of Poisons
0.06% of 4821 decks 3 decks
Ghave, Guru of Spores
0.03% of 6440 decks 2 decks
Hancock, Ghoulish Mayor
1.15% of 174 decks 2 decks
Meren of Clan Nel Toth
0.01% of 15166 decks 2 decks
Massacre Girl, Known Killer
0.05% of 4207 decks 2 decks
Grist, the Hunger Tide
0.04% of 5648 decks 2 decks
Ziatora, the Incinerator
0.01% of 8061 decks 1 decks
Kenrith, the Returned King
0.00% of 21799 decks 1 decks
Mikaeus, the Unhallowed
0.07% of 1365 decks 1 decks
Ayara, First of Locthwain
0.02% of 4856 decks 1 decks
Vraska, the Silencer
0.06% of 1546 decks 1 decks
Volo, Itinerant Scholar // Agent of the Iron Throne
3.12% of 32 decks 1 decks
Grenzo, Dungeon Warden
0.03% of 3292 decks 1 decks
Teysa Karlov
0.01% of 15616 decks 1 decks
Chatterfang, Squirrel General
0.01% of 16809 decks 1 decks
Sek'Kuar, Deathkeeper
0.07% of 1356 decks 1 decks
New Cards
Withering Torment
36% of 11 decks +17% synergy
Vengeful Bloodwitch
29% of 14 decks +27% synergy
High Synergy Cards
Young Wolf
92% of 26 decks +92% synergy
Fierce Guardianship
100% of 6 decks +82% synergy
Strangleroot Geist
77% of 26 decks +77% synergy
Mystical Tutor
83% of 6 decks +68% synergy
Swan Song
83% of 6 decks +67% synergy
Mystic Remora
83% of 6 decks +65% synergy
Mindbreak Trap
67% of 6 decks +63% synergy
Ranger-Captain of Eos
64% of 14 decks +60% synergy
Birds of Paradise
85% of 26 decks +58% synergy
Zulaport Cutthroat
67% of 60 decks +57% synergy
Top Cards
Dark Ritual
72% of 60 decks +49% synergy
Deflecting Swat
71% of 7 decks +55% synergy
Blood Artist
67% of 60 decks +55% synergy
Rhystic Study
67% of 6 decks +39% synergy
Deathrite Shaman
65% of 26 decks +53% synergy
Worldly Tutor
65% of 26 decks +51% synergy
Reanimate
62% of 60 decks +46% synergy
Chord of Calling
62% of 26 decks +56% synergy
Delighted Halfling
62% of 26 decks +47% synergy
Entomb
60% of 60 decks +53% synergy
Creatures
Ignoble Hierarch
100% of 3 decks +74% synergy
Orcish Bowmasters
60% of 60 decks +49% synergy
Devoted Druid
58% of 26 decks +55% synergy
Esper Sentinel
57% of 14 decks +37% synergy
Geralf's Messenger
57% of 60 decks +56% synergy
Avacyn's Pilgrim
55% of 11 decks +40% synergy
Thassa's Oracle
50% of 6 decks +43% synergy
Kutzil, Malamet Exemplar
50% of 8 decks +31% synergy
Warren Soultrader
48% of 29 decks +41% synergy
Wall of Roots
46% of 26 decks +45% synergy
Elves of Deep Shadow
46% of 26 decks +35% synergy
Eternal Witness
46% of 26 decks +25% synergy
Mikaeus, the Unhallowed
45% of 60 decks +42% synergy
Yawgmoth, Thran Physician
45% of 60 decks +41% synergy
Opposition Agent
43% of 60 decks +36% synergy
Aven Interrupter
43% of 7 decks +40% synergy
Grand Abolisher
43% of 14 decks +34% synergy
Dockside Extortionist
43% of 7 decks +31% synergy
Haywire Mite
42% of 26 decks +38% synergy
Llanowar Elves
42% of 26 decks +21% synergy
Bartolomé del Presidio
42% of 12 decks +35% synergy
Dauthi Voidwalker
40% of 60 decks +32% synergy
Heliod, Sun-Crowned
36% of 14 decks +32% synergy
Archivist of Oghma
36% of 14 decks +30% synergy
Drannith Magistrate
36% of 14 decks +29% synergy
Endurance
35% of 26 decks +32% synergy
Wight of the Reliquary
33% of 9 decks +25% synergy
Carrion Feeder
30% of 60 decks +25% synergy
Sheoldred, the Apocalypse
30% of 60 decks +24% synergy
Archon of Emeria
29% of 14 decks +26% synergy
Rosie Cotton of South Lane
29% of 14 decks +25% synergy
Pawn of Ulamog
28% of 60 decks +26% synergy
Gravecrawler
28% of 60 decks +26% synergy
Safehold Elite
27% of 11 decks +27% synergy
Kitchen Finks
27% of 11 decks +27% synergy
Protean Hulk
27% of 26 decks +25% synergy
Elvish Spirit Guide
27% of 26 decks +23% synergy
Elvish Mystic
27% of 26 decks +9% synergy
Pitiless Plunderer
27% of 60 decks +19% synergy
Gray Merchant of Asphodel
27% of 60 decks +18% synergy
Hancock, Ghoulish Mayor
24% of 38 decks +23% synergy
Forsaken Miner
24% of 34 decks +22% synergy
Viscera Seer
23% of 60 decks +14% synergy
Hapatra, Vizier of Poisons
23% of 26 decks +23% synergy
Collector Ouphe
23% of 26 decks +21% synergy
Sylvan Safekeeper
23% of 26 decks +20% synergy
Ophiomancer
22% of 60 decks +19% synergy
Icatian Moneychanger
21% of 14 decks +21% synergy
Vizier of Remedies
21% of 14 decks +21% synergy
White Plume Adventurer
21% of 14 decks +20% synergy
Instants
Vampiric Tutor
67% of 60 decks +48% synergy
Enlightened Tutor
57% of 14 decks +39% synergy
Culling the Weak
55% of 60 decks +51% synergy
Assassin's Trophy
54% of 26 decks +24% synergy
Mental Misstep
50% of 6 decks +44% synergy
Flusterstorm
50% of 6 decks +43% synergy
Pact of Negation
50% of 6 decks +43% synergy
Abrupt Decay
50% of 26 decks +39% synergy
Force of Will
50% of 6 decks +39% synergy
An Offer You Can't Refuse
50% of 6 decks +29% synergy
Cyclonic Rift
50% of 6 decks +22% synergy
Swords to Plowshares
50% of 14 decks -13% synergy
Eladamri's Call
45% of 11 decks +34% synergy
Silence
43% of 14 decks +36% synergy
Cabal Ritual
40% of 60 decks +35% synergy
Deadly Rollick
38% of 60 decks +28% synergy
Revitalizing Repast
38% of 8 decks +25% synergy
Force of Vigor
31% of 26 decks +27% synergy
Veil of Summer
31% of 26 decks +25% synergy
Legolas's Quick Reflexes
24% of 21 decks +21% synergy
Noxious Revival
23% of 26 decks +17% synergy
Crop Rotation
23% of 26 decks +13% synergy
Archdruid's Charm
21% of 14 decks +14% synergy
Fell the Profane
21% of 29 decks +9% synergy
Heroic Intervention
19% of 26 decks -10% synergy
Flare of Malice
17% of 30 decks +13% synergy
Songs of the Damned
15% of 60 decks +14% synergy
Sacrifice
13% of 60 decks +12% synergy
Dismember
13% of 60 decks +11% synergy
Fatal Push
12% of 60 decks +11% synergy
Snuff Out
12% of 60 decks +9% synergy
Imp's Mischief
12% of 60 decks +9% synergy
Ad Nauseam
12% of 60 decks +9% synergy
Defile
12% of 60 decks +8% synergy
Malakir Rebirth
12% of 60 decks +3% synergy
Consuming Corruption
11% of 27 decks +9% synergy
Saw in Half
10% of 60 decks +7% synergy
Deadly Dispute
10% of 60 decks -1% synergy
Mausoleum Secrets
8% of 60 decks +8% synergy
Rain of Filth
8% of 60 decks +8% synergy
Go for the Throat
8% of 60 decks +1% synergy
Infernal Grasp
8% of 60 decks +1% synergy
Village Rites
8% of 60 decks -2% synergy
Cut Down
7% of 60 decks +6% synergy
Force of Despair
7% of 60 decks +5% synergy
Sudden Spoiling
7% of 60 decks +5% synergy
Sheoldred's Edict
7% of 60 decks +4% synergy
Demonic Consultation
7% of 60 decks +3% synergy
Tainted Pact
7% of 60 decks +3% synergy
Sorceries
Demonic Tutor
72% of 60 decks +49% synergy
Gamble
57% of 7 decks +47% synergy
Diabolic Intent
57% of 60 decks +48% synergy
Eldritch Evolution
50% of 26 decks +45% synergy
Windfall
50% of 6 decks +37% synergy
Imperial Seal
45% of 60 decks +39% synergy
Toxic Deluge
43% of 60 decks +26% synergy
Vandalblast
43% of 7 decks +27% synergy
Faithless Looting
43% of 7 decks +26% synergy
Blasphemous Act
43% of 7 decks +9% synergy
Green Sun's Zenith
38% of 26 decks +32% synergy
Finale of Devastation
38% of 26 decks +30% synergy
Beseech the Mirror
33% of 60 decks +29% synergy
Buried Alive
30% of 60 decks +24% synergy
Lively Dirge
29% of 34 decks +27% synergy
Sevinne's Reclamation
29% of 14 decks +21% synergy
Agadeem's Awakening
28% of 60 decks +25% synergy
Unmarked Grave
25% of 60 decks +22% synergy
Grim Tutor
23% of 60 decks +19% synergy
Culling Ritual
23% of 26 decks +12% synergy
Unearth
22% of 60 decks +18% synergy
Idyllic Tutor
21% of 14 decks +17% synergy
Feed the Swarm
18% of 60 decks +0% synergy
Victimize
17% of 60 decks +5% synergy
Three Visits
15% of 26 decks -9% synergy
Final Parting
13% of 60 decks +12% synergy
Damnation
10% of 60 decks +2% synergy
Praetor's Grasp
8% of 60 decks +6% synergy
Infectious Inquiry
8% of 60 decks +6% synergy
Peer into the Abyss
8% of 60 decks +5% synergy
Dread Return
8% of 60 decks +3% synergy
Sign in Blood
8% of 60 decks -1% synergy
Chain of Smog
7% of 60 decks +5% synergy
Night's Whisper
7% of 60 decks -2% synergy
Utility Artifacts
Phyrexian Altar
50% of 60 decks +46% synergy
Birthing Pod
42% of 26 decks +40% synergy
Ashnod's Altar
40% of 60 decks +32% synergy
The One Ring
35% of 60 decks +26% synergy
Skullclamp
32% of 60 decks +19% synergy
Jet Medallion
28% of 60 decks +25% synergy
Wishclaw Talisman
28% of 60 decks +23% synergy
Sensei's Divining Top
22% of 60 decks +16% synergy
Bolas's Citadel
22% of 60 decks +13% synergy
Altar of Dementia
17% of 60 decks +14% synergy
The Great Henge
15% of 26 decks +5% synergy
Aetherflux Reservoir
13% of 60 decks +10% synergy
Vexing Bauble
11% of 27 decks +9% synergy
Genesis Chamber
10% of 60 decks +9% synergy
Lightning Greaves
10% of 60 decks -15% synergy
Thousand-Year Elixir
8% of 60 decks +6% synergy
Expedition Map
8% of 60 decks +5% synergy
The Ozolith
8% of 60 decks +5% synergy
Clown Car
7% of 60 decks +6% synergy
Defense Grid
7% of 60 decks +6% synergy
Enchantments
Insidious Roots
50% of 14 decks +42% synergy
Birthing Ritual
43% of 7 decks +42% synergy
Underworld Breach
43% of 7 decks +37% synergy
Sylvan Library
38% of 26 decks +27% synergy
The Meathook Massacre
33% of 60 decks +28% synergy
Animate Dead
33% of 60 decks +24% synergy
Deafening Silence
29% of 14 decks +26% synergy
Nest of Scarabs
28% of 60 decks +28% synergy
Survival of the Fittest
27% of 26 decks +25% synergy
Necropotence
23% of 60 decks +18% synergy
Necromancy
22% of 60 decks +19% synergy
Touch the Spirit Realm
21% of 14 decks +19% synergy
Smothering Tithe
21% of 14 decks -3% synergy
Utopia Sprawl
19% of 26 decks +12% synergy
Bastion of Remembrance
18% of 60 decks +12% synergy
Black Market Connections
18% of 60 decks +7% synergy
Chthonian Nightmare
17% of 30 decks +14% synergy
Earthcraft
15% of 26 decks +15% synergy
Carpet of Flowers
15% of 26 decks +12% synergy
Wild Growth
15% of 26 decks +4% synergy
Grave Pact
13% of 60 decks +9% synergy
Bridge from Below
12% of 60 decks +12% synergy
Carnival of Souls
12% of 60 decks +11% synergy
Blight Mound
12% of 60 decks +11% synergy
Bitterblossom
10% of 60 decks +6% synergy
Phyrexian Arena
10% of 60 decks -5% synergy
Dreadhorde Invasion
8% of 60 decks +6% synergy
Bloodchief Ascension
8% of 60 decks +5% synergy
Dictate of Erebos
8% of 60 decks +5% synergy
Case of the Stashed Skeleton
7% of 43 decks +6% synergy
Contamination
7% of 60 decks +6% synergy
Retribution of the Ancients
7% of 60 decks +6% synergy
Dance of the Dead
7% of 60 decks +5% synergy
Black Market
7% of 60 decks +2% synergy
Planeswalkers
Grist, the Hunger Tide
46% of 26 decks +42% synergy
Tyvar, Jubilant Brawler
38% of 26 decks +34% synergy
Utility Lands
Boseiju, Who Endures
69% of 26 decks +50% synergy
Ancient Tomb
67% of 60 decks +56% synergy
Otawara, Soaring City
67% of 6 decks +50% synergy
Shifting Woodland
62% of 8 decks +53% synergy
Phyrexian Tower
60% of 60 decks +51% synergy
Urborg, Tomb of Yawgmoth
52% of 60 decks +42% synergy
Minamo, School at Water's Edge
50% of 6 decks +46% synergy
Gaea's Cradle
46% of 26 decks +40% synergy
Urza's Saga
43% of 60 decks +36% synergy
Takenuma, Abandoned Mire
37% of 60 decks +26% synergy
Cabal Coffers
28% of 60 decks +18% synergy
Gavony Township
27% of 11 decks +18% synergy
Dryad Arbor
27% of 26 decks +23% synergy
Nykthos, Shrine to Nyx
27% of 60 decks +21% synergy
Lake of the Dead
23% of 60 decks +23% synergy
Yavimaya, Cradle of Growth
23% of 60 decks +14% synergy
Bojuka Bog
22% of 60 decks -9% synergy
Spymaster's Vault
21% of 29 decks +17% synergy
Emergence Zone
17% of 60 decks +14% synergy
Centaur Garden
15% of 26 decks +15% synergy
Command Beacon
15% of 60 decks +10% synergy
Blast Zone
12% of 60 decks +10% synergy
Field of the Dead
12% of 60 decks +8% synergy
Castle Locthwain
10% of 60 decks +5% synergy
Volrath's Stronghold
8% of 60 decks +7% synergy
Homeward Path
8% of 60 decks +7% synergy
Barad-dûr
8% of 60 decks +5% synergy
Cabal Stronghold
7% of 60 decks +3% synergy
Shizo, Death's Storehouse
7% of 60 decks +2% synergy
Mana Artifacts
Sol Ring
97% of 60 decks +12% synergy
Arcane Signet
68% of 60 decks -4% synergy
Talisman of Dominance
50% of 6 decks +19% synergy
Chrome Mox
48% of 60 decks +42% synergy
Mox Diamond
43% of 60 decks +39% synergy
Mana Vault
43% of 60 decks +37% synergy
Talisman of Indulgence
43% of 7 decks +17% synergy
Rakdos Signet
43% of 7 decks +13% synergy
Lotus Petal
40% of 60 decks +33% synergy
Mana Crypt
38% of 60 decks +30% synergy
Jeweled Lotus
32% of 60 decks +26% synergy
Talisman of Resilience
31% of 26 decks +19% synergy
Talisman of Hierarchy
29% of 14 decks +4% synergy
Mox Amber
27% of 60 decks +22% synergy
Mox Opal
27% of 60 decks +22% synergy
Fellwar Stone
23% of 60 decks +2% synergy
Springleaf Drum
15% of 60 decks +13% synergy
Golgari Signet
12% of 26 decks -1% synergy
Lion's Eye Diamond
10% of 60 decks +8% synergy
Grim Monolith
7% of 60 decks +5% synergy
Lands
Raucous Theater
100% of 4 decks +87% synergy
Blood Crypt
100% of 7 decks +61% synergy
Watery Grave
100% of 6 decks +59% synergy
Stomping Ground
100% of 3 decks +59% synergy
Overgrown Tomb
92% of 26 decks +50% synergy
Temple Garden
91% of 11 decks +51% synergy
Godless Shrine
86% of 14 decks +45% synergy
Underground Sea
83% of 6 decks +69% synergy
Undercity Sewers
75% of 4 decks +61% synergy
Morphic Pool
67% of 6 decks +41% synergy
Bayou
65% of 26 decks +52% synergy
Llanowar Wastes
65% of 26 decks +40% synergy
Undergrowth Stadium
65% of 26 decks +39% synergy
Scrubland
64% of 14 decks +51% synergy
Savannah
64% of 11 decks +51% synergy
Underground Mortuary
60% of 15 decks +44% synergy
Luxury Suite
57% of 7 decks +31% synergy
Command Tower
57% of 60 decks -17% synergy
Nurturing Peatland
54% of 26 decks +48% synergy
Verdant Catacombs
52% of 60 decks +40% synergy
Underground River
50% of 6 decks +30% synergy
Indatha Triome
45% of 11 decks +14% synergy
Gemstone Caverns
45% of 60 decks +40% synergy
Marsh Flats
45% of 60 decks +34% synergy
Bloodstained Mire
43% of 60 decks +33% synergy
Badlands
43% of 7 decks +29% synergy
Vault of Champions
43% of 14 decks +17% synergy
Polluted Delta
42% of 60 decks +30% synergy
Horizon Canopy
36% of 11 decks +32% synergy
Bountiful Promenade
36% of 11 decks +12% synergy
Cavern of Souls
35% of 60 decks +28% synergy
Talon Gates of Madara
35% of 26 decks +31% synergy
Shadowy Backstreet
30% of 10 decks +17% synergy
Silent Clearing
29% of 14 decks +24% synergy
Caves of Koilos
29% of 14 decks +0% synergy
Brushland
27% of 11 decks +11% synergy
Darkbore Pathway
27% of 26 decks +18% synergy
Woodland Cemetery
27% of 26 decks -1% synergy
Windswept Heath
27% of 60 decks +16% synergy
Exotic Orchard
27% of 60 decks -9% synergy
City of Brass
25% of 60 decks +17% synergy
Misty Rainforest
25% of 60 decks +13% synergy
Mana Confluence
23% of 60 decks +16% synergy
Blooming Marsh
23% of 26 decks +19% synergy
Deathcap Glade
23% of 26 decks +9% synergy
Wooded Foothills
22% of 60 decks +11% synergy
Shattered Sanctum
21% of 14 decks +8% synergy
Twilight Mire
19% of 26 decks +9% synergy
Flooded Strand
15% of 60 decks +4% synergy
Forbidden Orchard
12% of 60 decks +9% synergy