Grim Monolith + The Blackstaff of Waterdeep + Training Grounds

Grim Monolith
The Blackstaff of Waterdeep
Training Grounds

Requires
Grim Monolith must be on the battlefield. The Blackstaff of Waterdeep must be on the battlefield. Training Grounds must be on the battlefield. Grim Monolith does not have summoning sickness. Mana needed:
Steps
  1. Activate Grim Monolith's first ability by tapping it, adding .
  2. Activate The Blackstaff of Waterdeep by paying 1 and tapping it, causing Grim Monolith to become an artifact creature until end of turn.
  3. Activate Grim Monolith's second ability by paying 2, untapping it.
  4. Activate Grim Monolith's first ability by tapping it, adding .
  5. Repeat from step 3.
Results
Infinite colorless mana.

Urza, Lord High Artificer
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Katsumasa, the Animator
0.64% of 312 decks 2 decks
Memnarch
0.14% of 1469 decks 2 decks
Drafna, Founder of Lat-Nam
0.09% of 1057 decks 1 decks
Ravos, Soultender // Thrasios, Triton Hero
0.25% of 398 decks 1 decks
Mistform Ultimus
0.35% of 286 decks 1 decks
Sydri, Galvanic Genius
0.05% of 2180 decks 1 decks
Rograkh, Son of Rohgahh // Thrasios, Triton Hero
0.05% of 2087 decks 1 decks
Thrasios, Triton Hero // Tymna the Weaver
0.02% of 5622 decks 1 decks
Urza, Prince of Kroog
0.04% of 2658 decks 1 decks
Tevesh Szat, Doom of Fools // Thrasios, Triton Hero
0.06% of 1765 decks 1 decks
High Synergy Cards
Enlightened Tutor
100% of 4 decks +82% synergy
Forensic Gadgeteer
78% of 9 decks +74% synergy
Urza's Saga
64% of 14 decks +57% synergy
Voltaic Construct
50% of 14 decks +50% synergy
Rings of Brighthearth
50% of 14 decks +48% synergy
Cyclonic Rift
71% of 14 decks +43% synergy
Tezzeret, Betrayer of Flesh
43% of 14 decks +42% synergy
Minamo, School at Water's Edge
43% of 14 decks +39% synergy
The One Ring
46% of 13 decks +37% synergy
Flusterstorm
43% of 14 decks +36% synergy
Top Cards
Basalt Monolith
79% of 14 decks +76% synergy
Mox Opal
79% of 14 decks +74% synergy
Mana Vault
71% of 14 decks +65% synergy
Lotus Petal
57% of 14 decks +50% synergy
Rhystic Study
57% of 14 decks +29% synergy
Mox Amber
50% of 14 decks +46% synergy
Mox Diamond
43% of 14 decks +38% synergy
Everflowing Chalice
43% of 14 decks +38% synergy
Thran Dynamo
43% of 14 decks +38% synergy
Chrome Mox
43% of 14 decks +36% synergy
Creatures
Delighted Halfling
75% of 4 decks +61% synergy
Urza, Lord High Artificer
36% of 14 decks +33% synergy
Displacer Kitten
36% of 14 decks +30% synergy
Etherium Sculptor
36% of 14 decks +30% synergy
Hullbreaker Horror
36% of 14 decks +28% synergy
Palladium Myr
29% of 14 decks +26% synergy
Walking Ballista
29% of 14 decks +26% synergy
Padeem, Consul of Innovation
29% of 14 decks +25% synergy
Thassa's Oracle
29% of 14 decks +21% synergy
Karn, Silver Golem
21% of 14 decks +21% synergy
Pili-Pala
21% of 14 decks +21% synergy
Metalworker
21% of 14 decks +21% synergy
Katsumasa, the Animator
21% of 14 decks +21% synergy
Grand Architect
21% of 14 decks +21% synergy
Vedalken Archmage
21% of 14 decks +20% synergy
Unctus, Grand Metatect
21% of 14 decks +20% synergy
Spellskite
21% of 14 decks +18% synergy
The Reality Chip
21% of 14 decks +17% synergy
Phyrexian Metamorph
21% of 14 decks +14% synergy
Instants
Tainted Pact
75% of 4 decks +71% synergy
Path to Exile
75% of 4 decks +30% synergy
Mana Drain
50% of 14 decks +35% synergy
Force of Will
43% of 14 decks +32% synergy
Swan Song
43% of 14 decks +26% synergy
Whir of Invention
36% of 14 decks +33% synergy
Mindbreak Trap
36% of 14 decks +32% synergy
Dramatic Reversal
36% of 14 decks +30% synergy
Mental Misstep
36% of 14 decks +30% synergy
Pact of Negation
36% of 14 decks +28% synergy
Force of Negation
36% of 14 decks +27% synergy
Mystical Tutor
36% of 14 decks +21% synergy
Fierce Guardianship
36% of 14 decks +18% synergy
An Offer You Can't Refuse
36% of 14 decks +15% synergy
Counterspell
36% of 14 decks -7% synergy
Borne Upon a Wind
31% of 13 decks +27% synergy
March of Swirling Mist
21% of 14 decks +18% synergy
Chain of Vapor
21% of 14 decks +17% synergy
Dispel
21% of 14 decks +17% synergy
Muddle the Mixture
21% of 14 decks +16% synergy
Sorceries
Demonic Tutor
75% of 4 decks +53% synergy
Transmute Artifact
29% of 14 decks +28% synergy
Fabricate
29% of 14 decks +22% synergy
Rise and Shine
21% of 14 decks +20% synergy
Reshape
21% of 14 decks +20% synergy
Thoughtcast
21% of 14 decks +18% synergy
Utility Artifacts
Heartstone
36% of 14 decks +35% synergy
Manifold Key
36% of 14 decks +34% synergy
Sensei's Divining Top
36% of 14 decks +30% synergy
Lightning Greaves
36% of 14 decks +10% synergy
Imposter Mech
29% of 14 decks +27% synergy
Cloud Key
29% of 14 decks +27% synergy
Mystic Forge
29% of 14 decks +26% synergy
Winter Orb
21% of 14 decks +21% synergy
Defense Grid
21% of 14 decks +21% synergy
Clock of Omens
21% of 14 decks +20% synergy
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21% of 14 decks +20% synergy
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21% of 14 decks +20% synergy
Staff of Domination
21% of 14 decks +20% synergy
Sapphire Medallion
21% of 14 decks +19% synergy
Unwinding Clock
21% of 14 decks +19% synergy
Swiftfoot Boots
21% of 14 decks -6% synergy
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Mystic Remora
43% of 14 decks +25% synergy
Power Artifact
29% of 14 decks +28% synergy
Pemmin's Aura
21% of 14 decks +20% synergy
Planeswalkers
Karn, the Great Creator
29% of 14 decks +27% synergy
Jace, Wielder of Mysteries
21% of 14 decks +18% synergy
Utility Lands
Ancient Tomb
57% of 14 decks +47% synergy
Inventors' Fair
36% of 14 decks +32% synergy
Darksteel Citadel
36% of 14 decks +32% synergy
Academy Ruins
36% of 14 decks +31% synergy
Seat of the Synod
36% of 14 decks +29% synergy
Treasure Vault
29% of 14 decks +26% synergy
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29% of 14 decks +12% synergy
City of Traitors
21% of 14 decks +21% synergy
Crystal Vein
21% of 14 decks +20% synergy
Emergence Zone
21% of 14 decks +19% synergy
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86% of 14 decks +14% synergy
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50% of 14 decks +41% synergy
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36% of 14 decks +34% synergy
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Gilded Lotus
29% of 14 decks +25% synergy
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29% of 14 decks +12% synergy
Moonsnare Prototype
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21% of 14 decks +20% synergy
Springleaf Drum
21% of 14 decks +20% synergy
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21% of 14 decks +18% synergy
Jeweled Lotus
21% of 14 decks +15% synergy
Chromatic Lantern
21% of 14 decks +12% synergy
Lands
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75% of 4 decks +61% synergy
Hallowed Fountain
75% of 4 decks +34% synergy
Flooded Strand
50% of 14 decks +39% synergy
Polluted Delta
50% of 14 decks +39% synergy
Gemstone Caverns
43% of 14 decks +38% synergy
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43% of 14 decks +32% synergy
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Spire of Industry
29% of 14 decks +26% synergy
Mana Confluence
29% of 14 decks +21% synergy
Windswept Heath
29% of 14 decks +18% synergy
Misty Rainforest
29% of 14 decks +17% synergy
Cavern of Souls
21% of 14 decks +15% synergy
City of Brass
21% of 14 decks +13% synergy
Marsh Flats
21% of 14 decks +10% synergy
Verdant Catacombs
21% of 14 decks +10% synergy
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21% of 14 decks -14% synergy