OOC: I assume you mean 65Z or 35Z, I'm not sure which one. Anything else will bump into Darth or will not be in range for a bite.
As Crumbull approaches, Darth takes an AoO with a long tentacle. He misses (rolled 26).
Crumbull almost bites Darth's slimy head off (natural 20, 35-8 crit roll).
43 points of damage. Darth has 3 hp left.