At the beginning of your upkeep, you may exile Cosima. If you do, it gains "Whenever a land enters the battlefield under your control, if Cosima is exiled, you may put a voyage counter on it. If you don't return Cosima to the battlefield with X +1/+1 counters on it, where X is the number of voyage counters on it."
Whenever a Vehicle you control deals combat damage to a player, that player exiles that many cards from the top of their library. You may play lands from among those cards for as long as they remain exiled.