there's a really funny easter egg in ultrakill that has to do with the sandbox mode
the sandbox is designed to look almost identical to gm_construct, the default gmod map. (it's actually not any one version of construct, it pulls elements from a few different versions to try to be reminiscent of the "platonic" gm_construct, the one hakita thinks of when he thinks "gm_construct")
i laughed really really hard when i saw this, but it's actually not the easter egg i mean...