There and Back Again, Time Sieve, and Hex Parasite

Prerequisites

• There and Back Again on the battlefield
• Time Sieve on the battlefield
• Hex Parasite on the battlefield
• There and Back Again has exactly two lore counters on it
• You control a Smaug token, or you control five additional artifacts
• the first turn, with available the second turn if you do not control a Smaug token available

Steps

1. At the beginning of your precombat main phase, There and Back Again triggers, putting a lore counter on it, triggering its third chapter ability
2. Holding priority, activate Hex Parasite by paying , removing a lore counter from There and Back Again, and giving Hex Parasite +1/+0 until end of turn
3. Resolve the There and Back Again ability, creating a legendary 6/6 Smaug creature token
4. If you control two Smaugs, put one into your graveyard due to the legend rule
5. If a Smaug dies this way, it triggers, creating fourteen Treasure tokens
6. Activate Time Sieve by tapping it and sacrificing five other artifacts, causing you to take an extra turn after this one
7. Repeat each turn

Results

• Infinite turns