Soul of Windgrace, Waves of Aggression, and Klauth, Unrivaled Ancient

Prerequisites

• Soul of Windgrace on the battlefield
• Waves of Aggression in the graveyard
• Klauth, Unrivaled Ancient on the battlefield
• An opponent cannot block and kill Klauth or Soul of Windgrace
• Soul of Windgrace does not have summoning sickness
• You have at least one land card in your graveyard

Steps

1. Declare Klauth and Soul of Windgrace as attackers, triggering their abilities
2. Resolve the Klauth trigger, adding at least that can only be spent to cast spells
3. Resolve the Soul of Windgrace trigger, returning a land card from your graveyard to the battlefield tapped
4. Move to your postcombat main phase
5. Cast Waves of Aggression from your graveyard for its retrace cost by paying and discarding a land card, causing you to untap all creatures that attacked this turn, and to get an additional combat and main phase after this one
6. Repeat

Results

• Infinite colored mana that can only be spent to cast spells
• Infinite combat phases
• Infinite magecraft triggers
• Infinite self-discard triggers
• Infinite storm count