Agatha's Soul Cauldron + Spike Feeder + Ajani's Pridemate

Agatha's Soul Cauldron
Spike Feeder
Ajani's Pridemate

Requires
Agatha's Soul Cauldron must be on the battlefield. Spike Feeder must be in exile (exiled by Agatha's Soul Cauldron). Ajani's Pridemate must be on the battlefield. Ajani's Pridemate has at least one +1/+1 counter on it.
Steps
  1. Activate Ajani's Pridemate using Spike Feeder's second ability by removing a +1/+1 counter from it, causing you to gain 2 life.
  2. Ajani's Pridemate triggers, putting a +1/+1 counter on itself.
  3. Repeat.
Results
Infinite lifegain. Infinite lifegain triggers.

Trelasarra, Moon Dancer
0.09% of 2287 decks 2 decks
Shalai and Hallar
0.07% of 8115 decks 6 decks
Lathiel, the Bounteous Dawn
0.07% of 4443 decks 3 decks
Kenrith, the Returned King
0.01% of 20593 decks 2 decks
High Synergy Cards
Basking Broodscale
100% of 5 decks +99% synergy
Walking Ballista
86% of 14 decks +83% synergy
Archangel of Thune
79% of 14 decks +77% synergy
Heliod, Sun-Crowned
79% of 14 decks +77% synergy
The Ozolith
79% of 14 decks +75% synergy
The Red Terror
75% of 8 decks +75% synergy
All Will Be One
75% of 8 decks +73% synergy
Hardened Scales
71% of 14 decks +67% synergy
Dockside Extortionist
75% of 8 decks +67% synergy
Scurry Oak
64% of 14 decks +63% synergy
Top Cards
Ozolith, the Shattered Spire
64% of 14 decks +61% synergy
Kami of Whispered Hopes
64% of 14 decks +61% synergy
Esper Sentinel
64% of 14 decks +55% synergy
War Elemental
62% of 8 decks +62% synergy
Deflecting Swat
62% of 8 decks +55% synergy
Cleric Class
57% of 14 decks +56% synergy
Worldly Tutor
57% of 14 decks +51% synergy
Swords to Plowshares
57% of 14 decks +29% synergy
Quest for Pure Flame
50% of 8 decks +50% synergy
Triskelion
50% of 14 decks +50% synergy
Creatures
Voice of the Blessed
50% of 14 decks +49% synergy
Ivy Lane Denizen
50% of 14 decks +49% synergy
Trelasarra, Moon Dancer
43% of 14 decks +43% synergy
Essence Warden
43% of 14 decks +42% synergy
Vigor
43% of 14 decks +42% synergy
Soul Warden
43% of 14 decks +40% synergy
Birds of Paradise
43% of 14 decks +30% synergy
Celestial Unicorn
36% of 14 decks +36% synergy
Wildwood Scourge
36% of 14 decks +35% synergy
Emiel the Blessed
36% of 14 decks +35% synergy
Conclave Mentor
36% of 14 decks +35% synergy
Rosie Cotton of South Lane
36% of 14 decks +34% synergy
Kutzil, Malamet Exemplar
30% of 10 decks +25% synergy
Speaker of the Heavens
29% of 14 decks +28% synergy
Prosperous Innkeeper
29% of 14 decks +27% synergy
Soul's Attendant
29% of 14 decks +27% synergy
Champion of Lambholt
29% of 14 decks +25% synergy
Delighted Halfling
29% of 14 decks +22% synergy
Phyrexian Devourer
21% of 14 decks +21% synergy
Enduring Scalelord
21% of 14 decks +21% synergy
Herd Baloth
21% of 14 decks +21% synergy
Good-Fortune Unicorn
21% of 14 decks +21% synergy
Daxos, Blessed by the Sun
21% of 14 decks +20% synergy
Abzan Falconer
21% of 14 decks +20% synergy
Devoted Druid
21% of 14 decks +20% synergy
Suture Priest
21% of 14 decks +20% synergy
Shalai, Voice of Plenty
21% of 14 decks +20% synergy
Gyre Sage
21% of 14 decks +20% synergy
Serra Ascendant
21% of 14 decks +20% synergy
Temur Sabertooth
21% of 14 decks +20% synergy
Destiny Spinner
21% of 14 decks +19% synergy
Archivist of Oghma
21% of 14 decks +18% synergy
Drannith Magistrate
21% of 14 decks +18% synergy
Bloom Tender
21% of 14 decks +18% synergy
Ornithopter of Paradise
21% of 14 decks +17% synergy
Eternal Witness
21% of 14 decks +11% synergy
Instants
Red Elemental Blast
50% of 8 decks +47% synergy
Lightning Bolt
50% of 8 decks +45% synergy
Enlightened Tutor
50% of 14 decks +42% synergy
Path to Exile
43% of 14 decks +22% synergy
Seething Song
38% of 8 decks +35% synergy
Pyroblast
38% of 8 decks +34% synergy
Abrade
38% of 8 decks +32% synergy
Eladamri's Call
36% of 14 decks +33% synergy
Silence
36% of 14 decks +33% synergy
Generous Gift
36% of 14 decks +24% synergy
Heroic Intervention
36% of 14 decks +22% synergy
Tamiyo's Safekeeping
29% of 14 decks +25% synergy
Beast Within
29% of 14 decks +10% synergy
Nature's Claim
21% of 14 decks +17% synergy
Sorceries
Gamble
50% of 8 decks +45% synergy
Faithless Looting
38% of 8 decks +29% synergy
Jeska's Will
38% of 8 decks +29% synergy
Farseek
29% of 14 decks +13% synergy
Damning Verdict
21% of 14 decks +21% synergy
Finale of Devastation
21% of 14 decks +18% synergy
Three Visits
21% of 14 decks +10% synergy
Nature's Lore
21% of 14 decks +6% synergy
Utility Artifacts
Shadowspear
29% of 14 decks +25% synergy
Aetherflux Reservoir
29% of 14 decks +25% synergy
Swiftfoot Boots
29% of 14 decks +1% synergy
Trinisphere
21% of 14 decks +21% synergy
Well of Lost Dreams
21% of 14 decks +20% synergy
The Great Henge
21% of 14 decks +17% synergy
Enchantments
Smothering Tithe
50% of 14 decks +38% synergy
Light of Promise
43% of 14 decks +42% synergy
Branching Evolution
43% of 14 decks +41% synergy
Mayael's Aria
38% of 8 decks +37% synergy
Survival of the Fittest
29% of 14 decks +28% synergy
Cathars' Crusade
29% of 14 decks +26% synergy
Sylvan Library
29% of 14 decks +23% synergy
Ajani's Welcome
21% of 14 decks +21% synergy
Dawn of Hope
21% of 14 decks +21% synergy
Carpet of Flowers
21% of 14 decks +20% synergy
Authority of the Consuls
21% of 14 decks +19% synergy
Planeswalkers
Ajani, the Greathearted
29% of 14 decks +28% synergy
Utility Lands
Gavony Township
50% of 14 decks +48% synergy
Urza's Saga
29% of 14 decks +21% synergy
Ancient Tomb
29% of 14 decks +18% synergy
Strip Mine
21% of 14 decks +18% synergy
Karn's Bastion
21% of 14 decks +16% synergy
Boseiju, Who Endures
21% of 14 decks +12% synergy
Mana Artifacts
Sol Ring
86% of 14 decks +1% synergy
Arcane Signet
64% of 14 decks -7% synergy
Talisman of Impulse
38% of 8 decks +36% synergy
Jeweled Lotus
36% of 14 decks +28% synergy
Mana Crypt
36% of 14 decks +25% synergy
Chrome Mox
29% of 14 decks +22% synergy
Pristine Talisman
21% of 14 decks +20% synergy
Lands
Command Tower
79% of 14 decks +5% synergy
Taiga
75% of 8 decks +72% synergy
Stomping Ground
75% of 8 decks +66% synergy
Plateau
62% of 8 decks +60% synergy
Jetmir's Garden
62% of 8 decks +58% synergy
Savannah
57% of 14 decks +54% synergy
Temple Garden
57% of 14 decks +48% synergy
Sacred Foundry
50% of 8 decks +42% synergy
Windswept Heath
50% of 14 decks +40% synergy
Wooded Foothills
43% of 14 decks +33% synergy
Cragcrown Pathway
38% of 8 decks +35% synergy
Needleverge Pathway
38% of 8 decks +35% synergy
Karplusan Forest
38% of 8 decks +34% synergy
Rootbound Crag
38% of 8 decks +32% synergy
Battlefield Forge
38% of 8 decks +32% synergy
Spectator Seating
38% of 8 decks +32% synergy
Clifftop Retreat
38% of 8 decks +32% synergy
Canopy Vista
36% of 14 decks +28% synergy
Arid Mesa
36% of 14 decks +25% synergy
Branchloft Pathway
29% of 14 decks +27% synergy
Brushland
29% of 14 decks +25% synergy
Blossoming Sands
21% of 14 decks +20% synergy
Sunpetal Grove
21% of 14 decks +16% synergy
Bountiful Promenade
21% of 14 decks +16% synergy
Mana Confluence
21% of 14 decks +14% synergy
City of Brass
21% of 14 decks +13% synergy