I do, indeed, have a changed version of the Diger. It is in my PotSP conversion:
Diger (1): CR 2; Large Ooze; HD 2d10+4; hp 14; Init -3 (Dex); Spd 5 ft., 30 ft. fly (poor), 40 ft. swim; AC 11 (-1 size, -3 Dex, +5 natural); Atk Touch +6 melee (paralysis); Face 15 ft. by 15 ft.; SA Paralysis, Engulf; SQ Limited Flight, Ooze; AL N; SV Fort +2, Ref -2, Will -5; Str 21, Dex 4, Con 15, Int -, Wis 1, Cha 1.
SA— Paralysis (Ex): Fort save (DC 13) or be paralyzed for 1d6 rounds; if engulfed, paralyzed for as long as foe remains engulfed. Engulf (Ex): An engulfed opponent suffers 1d4 points of acid damage every 10 minutes.
SQ— Limited Flight (Ex): Can only fly for 1+1/2 Con rounds before it must rest for three times as long as it flew.
The diger doesn't do hit point damage, but if it paralyzes you, you're slowly eaten alive.