Here is an OSR version of Dave Hargrave’s Octorilla, from Arduin. Click here for a Dungeons and Dragons 5th edition version of the Octorilla.
This is conversion for OSR systems like Swords and Wizardry, Labyrinth Lord, and Lamentations of the Flame Princess.
Large Mutant Gorilla/Octopus AL N, MV 120’ (40’), AC 6, HD 4+1, Attacks:7 (8 tentacles, 1 bite), DM 1d3/1d6, THAC0: 15, Save: 10, HP:18.
Hit by a tentacle a creature becomes grappled. The Octorilla can then apply 1d4 constriction damage to that creature each turn there after. There is a 25% chance a grappled character will have it’s arms pinned, in which case it cannot attack. A grappled creature may try to break the grapple by:
Rolling 1d6 per hit die against the Octorilla’s 4 HD (4d6).
The Octorilla may throw a grappled character up to 20′ inflicting 1d6 damage, or apply it’s bit attack with an automatic hit.
Creatures may attack the Octorillas tentacles, each of which has 8 hit points, and an AC of 4.