Feldon of the Third Path + Timestream Navigator

Prerequisites

Feldon of the Third Path does not have summoning sickness. You control at least eight other permanents and/or have the city's blessing.

Steps

1. Activate Feldon by paying {2}{R} and tapping it, creating a token copy of Timestream Navigator with haste.
2. If you do not have the city's blessing, the Timestream Navigator token's ascend ability triggers, causing you to get the city's blessing for the rest of the game.
3. Activate the Timestream Navigator token by paying {2}{U}{U}, tapping it and putting it on the bottom of your library, causing you to take an extra turn after this one.
4. Repeat each turn.