At the Apple Worldwide Developers Conference today, Microsoft and Mojang showed off the first ever real-time gameplay for Minecraft Earth. Minecraft Earth is Microsoft’s new augmented reality game where players can overlay a blocky universe over the real world.. This new game comes out this summer for iOS and Android devices.

The demo starts with two developers building a small castle on a desk. The players are able to delete pieces and create new structures through their phones. At one point, the players even look at each other to see what their friend is using. After one player drops her avatar in the world, the other player’s phone reads her actions, and her avatar responds in kind.

After the desk demonstration, the developers scale the castle up. Instead of poking at a small castle model on a desk, the castle moves to take up the entire stage. The players then stand inside the castle and can walk around the digital space. As the presentation unfolds, the ground under the players explodes to reveal a cave. One of the developers gets in an archer battle with the skeletons underground before getting blown up by a Creeper enemy.

Players still need to gather building materials by walking around their actual neighborhoods and engaging in adventures. But once players have all the pieces they need, they can build virtually anything in the game’s AR system.