A good labyrinth means even the creator has issues. It'd be boring otherwise.

[He makes a face at the kid's question] Oh, a 'gift' from the Singularity, apparently. If there's any sentience to that damn rock it probably thought it was funny. [He doesn't need any reminder of "Angel Radio" it's bad enough that he isn't the only one of his kind here.] You'll be lucky if it doesn't do something to you that utterly wrecks your ability to be stealthy.

[Maybe turn him into a pyro like it did Wilhelm. But arguably that's been a greater problem.]