Unctus, Grand Metatect, The Watcher in the Water, and Grand Architect

Prerequisites

• Unctus, Grand Metatect on the battlefield
• The Watcher in the Water on the battlefield
• Grand Architect on the battlefield
• It is an opponent's turn

Steps

1. During an opponent's turn, activate Grand Architect by tapping a blue creature you control except Unctus, adding that can only be spent to cast artifact spells or to activate abilities of artifacts
2. The creature triggers, causing you to loot
3. The Watcher's first ability triggers, creating a 1/1 Tentacle creature token
4. Repeat

Results

• Infinite self-discard triggers
• Near-infinite ETB
• Infinite draw triggers
• Infinite looting
• Near-infinite tapped creature tokens
• Near-infinite colorless mana that can only be spent to cast artifact spells
• Near-infinite colorless mana that can only be spent to activate abilities of artifacts