Teysa, Orzhov Scion, Phyrexian Altar, and Reassembling Skeleton

Prerequisites

• Teysa, Orzhov Scion on the battlefield
• Phyrexian Altar on the battlefield
• Reassembling Skeleton in the graveyard

Steps

1. Activate Phyrexian Altar by sacrificing Reassembling Skeleton, adding When Reassembling Skeleton dies, Teysa triggers, creating a 1/1 white Spirit creature token Activate Phyrexian Altar by sacrificing the Spirit, adding one mana of any color
2. Activate Reassembling Skeleton by paying , returning it from your graveyard to the battlefield
3. Repeat

Results

• Infinite LTB
• Infinite ETB
• Infinite sacrifice triggers
• Infinite death triggers