The quad is insane - pick an enemy within a number of inches equal to the value of the Ability. It can't activate this turn. Being able to turn off a fighter for no dice roll is nuts, and the cat isn't bad in combt anyways.
I could see using the Crusher in Cabal, where I have a lot of little chumps to run around with, but I don't see a huge amount of "need" for either in a list. Both have uses, whether you'd like a tanky beatstick or a tricky cat.
A Kharibdyss can make a reasonable horde-killer with the -2 bravery Bloodline and it's own innate horde clearing, but most blobs have ways to ignore or reduce bravery tests anyways. The Hydra is fine as a nice little deathball, not as much as a Dragon but reasonable for the points. Anvilgard is clearly the best if you're going to take one, though, might as well get impact hits on a 2+.