Core Sentry is an enemy mob found in Forlorn Metropolis sub-biome dungeons in The Sunken Sea. They respawn periodically on Urban Moss.
They initially stand inactive until a player approaches closely or they take damage. They then have a short powering up animation and sound effect, which can be aborted by quickly backing out of aggro range again.
They attack with a 3 way fork of bright projectiles, spawned as they stomp a foot. They may also stomp attack without projectiles, for opponents at point blank range. They have a slow move speed but very high health that may be topped up by nearby Caveling Scholars.