Magewright's Stone, Synod Artificer, and Nyx Lotus

Prerequisites

• Magewright's Stone on the battlefield
• Synod Artificer on the battlefield
• Nyx Lotus on the battlefield
• Synod Artificer does not have summoning sickness
• Your have at least four devotion to any color

Steps

1. Activate Nyx Lotus by tapping it, adding at least four mana of any color with which you have devotion
2. Activate Synod Artificer's second ability by paying and tapping it, untapping Nyx Lotus and Magewright's Stone
3. Activate Magewright's Stone by paying and tapping it, untapping Synod Artificer
4. Repeat

Results

• Infinite mana among colors with which you have devotion
• Infinite untap of noncreature artifacts you control