Board Thread:Questions and Answers/@comment-108.32.188.194-20130420011438/@comment-5319459-20130420014452

The Vorpal and Disjunction enchantments are added by RedPower 2.

Vorpal, gives a chance for a mob (and possibly player) to drop their head when killed from an attack.

Disjunction, I think, stops endermen from teleporting once hit.