Spooky action has invaded the world of Minecraft. Google’s Quantum Artificial Intelligence Lab last week released a version of the popular computer game designed to teach players about the weird principles of quantum mechanics.

In regular Minecraft, players explore a 3D world made from blocks of different materials. They can use the pieces to build any structure imaginable, from a small wooden hut to a replica of Star Trek‘s USS Enterprise. Players can also modify the game to bring in new content, such as different types of blocks, or to alter gameplay, like adding in natural disasters. In 2011, a group at MIT created an addition to the game that lets users 3D-print their virtual creations.

Google’s modification, qCraft, adds blocks with a quantum twist. Some can have multiple possible properties and will change their appearance based on when they are observed, linked to the quantum concept of superposition. Pairs of blocks can also be entangled, so that the appearance of one will influence that of another no matter how far apart they are in the virtual world.

The Google team acknowledges that the Minecraft mod is primarily a teaching tool that relies on analogies to highlight quantum effects. “qCraft isn’t a perfect scientific simulation, but it’s a fun way for players to experience a few parts of quantum mechanics outside of thought experiments or dense textbook examples,” ‘the team announced.

In the real world, Google’s lab has reportedly been busy using a quantum computer to refine the controls for its wearable computer, Glass.