Gilded Lotus, Umbral Mantle, and Xenic Poltergeist

Prerequisites

• Gilded Lotus on the battlefield
• Umbral Mantle on the battlefield
• Xenic Poltergeist on the battlefield
• Gilded Lotus and Xenic Poltergeist does not have summoning sickness

Steps

1. Activate Xenic Poltergeist by tapping it, targeting Gilded Lotus
2. Activate Umbral Mantle's equip ability by paying , attaching it to the Gilded Lotus
3. Activate Gilded Lotus by tapping it, adding three mana of any one color
4. Activate Umbral Mantle by paying and untapping it, giving itself +2/+2 until end of turn
5. Repeat

Results

• Infinitely large Gilded Lotus until end of turn