User blog comment:A, Mori/Decalogue Pet Contest/@comment-1713909-20140311172153/@comment-16075172-20140312160738

Hellvent uses Melforce to create a protective vacuum around itself and protect against Cassiopeia's descending foot.

Hellvent, being the tenth part of Decalogue, is able to access the powers of all the others. It can only access one power at a time, but it still proves useful.