Clever Impersonator + Copy Enchantment + Oblivion Ring + Sage of Mysteries

Clever Impersonator
Copy Enchantment
Oblivion Ring
Sage of Mysteries

Requires
Clever Impersonator must be in hand. Copy Enchantment must be in hand. Oblivion Ring must be on the battlefield. Sage of Mysteries must be on the battlefield. Mana needed: 4
Steps
  1. Cast Copy Enchantment by paying 2.
  2. Copy Enchantment enters the battlefield, triggering Sage of Mysteries and itself.
  3. Resolve the Altar of Brood trigger, causing each opponent to mill a card.
  4. Resolve the Copy Enchantment's trigger, becoming a copy of Oblivion Ring and exiling Oblivion Ring.
  5. Cast Clever Impersonator by paying 2.
  6. Clever Impersonator enters the battlefield, triggering Sage of Mysteries and itself.
  7. Resolve the Altar of Brood trigger, causing each opponent to mill a card.
  8. Resolve the Clever Impersonator's trigger, becoming a copy of Copy Enchantment and exiling Copy Enchantment.
  9. Copy Enchantment leaves the battlefield, returning Oblivion Ring from exile to the battlefield.
  10. Sage of Mysteries and Oblivion Ring triggers.
  11. Resolve the Altar of Brood trigger, causing each opponent to mill a card.
  12. Resolve the Oblivion Ring's trigger, exiling Clever Impersonator.
  13. Clever Impersonator leaves the battlefield, returning Copy enchantment from exile to the battlefield.
  14. Repeat from step 2.
Results
Infinite ETB. Infinite LTB. Infinite mill.

The Master of Keys
0.04% of 2436 decks 1 decks
Marina Vendrell
0.02% of 4317 decks 1 decks
Top Commanders
Tuvasa the Sunlit
0.02% of 5045 decks 1 decks
Grand Arbiter Augustin IV
0.01% of 7099 decks 1 decks
Abdel Adrian, Gorion's Ward // Candlekeep Sage
0.03% of 2938 decks 1 decks
Sydri, Galvanic Genius
0.05% of 2180 decks 1 decks
Estrid, the Masked
0.03% of 3077 decks 1 decks
Tameshi, Reality Architect
0.04% of 2485 decks 1 decks
Alela, Artful Provocateur
0.01% of 12134 decks 1 decks
Lulu, Loyal Hollyphant // Candlekeep Sage
0.74% of 136 decks 1 decks
Ranar the Ever-Watchful
0.03% of 3584 decks 1 decks
High Synergy Cards
Grim Guardian
100% of 4 decks +99% synergy
Mirrormade
100% of 11 decks +98% synergy
Estrid's Invocation
82% of 11 decks +81% synergy
Altar of the Brood
64% of 11 decks +62% synergy
Enchanted Evening
45% of 11 decks +44% synergy
Sigil of the Empty Throne
45% of 11 decks +42% synergy
Archon of Sun's Grace
45% of 11 decks +42% synergy
Idyllic Tutor
45% of 11 decks +40% synergy
Mystic Remora
55% of 11 decks +37% synergy
Leonin Relic-Warder
36% of 11 decks +36% synergy
Top Cards
Swords to Plowshares
73% of 11 decks +10% synergy
Propaganda
45% of 11 decks +34% synergy
Ghostly Prison
45% of 11 decks +34% synergy
An Offer You Can't Refuse
45% of 11 decks +25% synergy
Rhystic Study
45% of 11 decks +18% synergy
Path to Exile
45% of 11 decks -0% synergy
Detention Sphere
36% of 11 decks +35% synergy
Ajani's Chosen
36% of 11 decks +35% synergy
Seal of Cleansing
36% of 11 decks +35% synergy
Starfield of Nyx
36% of 11 decks +35% synergy
Creatures
Sythis, Harvest's Hand
100% of 3 decks +92% synergy
Doomwake Giant
75% of 4 decks +73% synergy
Mesa Enchantress
36% of 11 decks +32% synergy
Abdel Adrian, Gorion's Ward
33% of 9 decks +32% synergy
Thassa's Devourer
27% of 11 decks +27% synergy
Sun Titan
27% of 11 decks +17% synergy
Instants
Enlightened Tutor
36% of 11 decks +19% synergy
Arcane Denial
36% of 11 decks +17% synergy
Generous Gift
36% of 11 decks +11% synergy
Counterspell
36% of 11 decks -7% synergy
Dovin's Veto
27% of 11 decks +8% synergy
Sorceries
Supreme Verdict
27% of 11 decks +13% synergy
Utility Artifacts
Wayfarer's Bauble
27% of 11 decks +17% synergy
Enchantments
Fertile Ground
100% of 3 decks +96% synergy
Sterling Grove
100% of 3 decks +92% synergy
Aura of Silence
36% of 11 decks +34% synergy
Grasp of Fate
36% of 11 decks +33% synergy
Sphere of Safety
36% of 11 decks +32% synergy
Blind Obedience
36% of 11 decks +30% synergy
Smothering Tithe
36% of 11 decks +11% synergy
Confounding Conundrum
27% of 11 decks +27% synergy
Banishing Light
27% of 11 decks +26% synergy
Hallowed Haunting
27% of 11 decks +26% synergy
Touch the Spirit Realm
27% of 11 decks +25% synergy
All That Glitters
27% of 11 decks +22% synergy
Utility Lands
Hall of Heliod's Generosity
36% of 11 decks +30% synergy
Reliquary Tower
36% of 11 decks +7% synergy
Mana Artifacts
Sol Ring
82% of 11 decks -3% synergy
Orzhov Signet
75% of 4 decks +48% synergy
Dimir Signet
75% of 4 decks +45% synergy
Arcane Signet
73% of 11 decks +1% synergy
Fellwar Stone
55% of 11 decks +33% synergy
Azorius Signet
55% of 11 decks +28% synergy
Talisman of Progress
45% of 11 decks +23% synergy
Mind Stone
36% of 11 decks +19% synergy
Lands
Seaside Citadel
100% of 3 decks +74% synergy
Spara's Headquarters
100% of 3 decks +68% synergy
Command Tower
91% of 11 decks +17% synergy
Sea of Clouds
55% of 11 decks +28% synergy
Exotic Orchard
55% of 11 decks +19% synergy
Hallowed Fountain
55% of 11 decks +14% synergy
Deserted Beach
45% of 11 decks +29% synergy
Glacial Fortress
45% of 11 decks +20% synergy
Prairie Stream
45% of 11 decks +12% synergy
Flooded Strand
36% of 11 decks +26% synergy
Port Town
36% of 11 decks +21% synergy
Polluted Delta
27% of 11 decks +16% synergy
Marsh Flats
27% of 11 decks +16% synergy
Temple of Enlightenment
27% of 11 decks +11% synergy
Adarkar Wastes
27% of 11 decks +10% synergy