Timestream Navigator is a mythic Creature — Human Pirate Wizard card from The Lost Caverns of Ixalan Commander (LCC), collector number 178. Current market price: $0.32, TCGplayer market prices via Scryfall.
Ascend (If you control ten or more permanents, you get the city's blessing for the rest of the game.) {2}{U}{U}, {T}, Put this creature on the bottom of its owner's library: Take an extra turn after this one. Activate only if you have the city's blessing.