These four show up often enough that the current guide gives them direct counters. Point costs are from the bestiary, not from the guide.
Drone (1 point, common)
Drone walks slowly toward the nearest Delver and hums. The hum is the location cue. On a tight map it can sit in a corridor for a long time, so plan a route that does not depend on that hallway. Entities cannot open doors, so a closing door can lock Drone in a room.
Lungwort (2 points, common)
Lungwort sees well and hears badly. On sight it chases and fires a spore in a straight line. The spore hits the first Delver for 5 damage and -5 speed. Check corners with the camera before you turn them. If it sees you, run on a diagonal so the spore misses.
Mimic (2 points, common)
A Mimic copies a Delver, or rarely appears as a skinless Robloxian. Tells are nonsense chat, a stiff walk, and an occasional giggle. A copied Mimic approaches slowly while you look at it. Back away while keeping line of sight. If you break line of sight, it chases. A skinless Mimic laughs and chases immediately.
Have the real team hold an item. A Mimic will not copy that. Changing your Roblox avatar after the run has started makes Mimics copy the new avatar instead of the body you are using.
Grappler (1 point, common)
On sight, Grappler screeches and fires a hook. A hit reels you in. Interact with the hook 12 times or you die. You can still trip traps while being reeled. After you break the hook, Grappler loses interest if you also break line of sight. The hook is accurate but short and slow enough to dodge if you already have distance.
While you are in a task
Teratoma is the rare entity the guide calls exceptionally quiet. Do not start a long minigame, especially Generator, Minesweeper, or Simon Says, without checking the corner. Warden is the sound-reactive one: both success and failure can pull it in.