Thought I’d join in with the Monday Monster theme:
These invisible creatures, if seen, resemble a cross between an octopus and a crab, with claws and tentacles that allow it to move by undulating across the floor. They feed on fear and anger, and use their natural invisibility to foster such emotions.
% Lair None
Dungeon Encounter Solitary (1) / None
Wilderness Encounter None
Movement 120’ (40’)
Armour Class 2
Hit Dice 4**
Attacks 3 (2 claws, tentacles)
Damage 1d6/1d6 and strangulation
Treasure Type None
Naturally invisible (thus difficult to hit, all attacks against the Entity are at -4), these alien creatures feed on fear and rage, inducing such feelings by telepathy. Once per turn an Invisible Entity can cast Confusion (as the spell), and can cast Cause Fear every three rounds. If confronted and cornered, it will fight, using its claws and tentacles. If the tentacle hits, the target must save versus paralysation or be grappled, suffering 1d6 strangulation damage each round until a new save is made or the entity releases the victim (by killing it, or making it flee).