The first half of Ark: Genesis, the new two-part expansion for Ark: Survival Evolved, has arrived, bringing with it a new map and biomes, an AI companion, new dinosaurs and creatures, and those massive turtles you can build a base on top of. (And if you need a few pointers, here's how to tame Megachelon, the giant sea turtle, in Ark: Genesis.)

The arrival of Genesis also brings an added bonus for those who have never played Ark before. The base game of Ark: Survival Evolved is free to play from now until Monday on Steam. And if you want to keep playing after the weekend, Ark is on sale for 80 percent off until Monday, too.

While the free weekend and sale doesn't include Genesis, it does include earlier expansion packs—Extinction, Aberration, and Scorched Earth—which are all marked down by 50 percent. You can take a peek at what Genesis has to offer in its launch trailer below. The second part of Genesis is planned for this winter.