Mega Audino from B- ===> C rank
Its almost entirely outclassed by Cresselia, because it takes mega slot. It does have few niches over it, though, but thinking that it eats up Mega Slot, i dont know, on 95% of teams its not worth it. However, it might work on defensive TR teams, it has some nice moves over Cress, most notably Heal Pulse, also Simple Beam to make something like QD Volcarona have 1 turn Geomancys without need to use Power Herb, and overall little better typing than Cress, but thats pretty much it.
Dragalge from E ===> C+ rank
Adaptability is released, so this guy deserves to rise in C+ rank. Adaptability Draco Meteor is one of the most hardest hitting things in the metagame. It has decent movepool, nice bulk (though low HP) and cool typing. It, however, it NEEDS TR to work at all. Its like Mega Ampharos, its monster in Trick Room and with right support, but outside it, despite its power, its almost dead weight.
Mega Altaria from E ===> C+ rank
Gonna try again to raise this guy. Mega Mence is gone, and this thing seems to be somehow okay alternative to it. It has access to DD + Return / Double-Edge aswell, despite not nearly as powerful as Mega Mence, it still hits like truck after +1, and has nice coverage moves like EQ. It can run special sets, too. Special would be outclassed by Sylveon, though, but M-Altaria gets some nice things like Fire Blast, Tailwind and Roost. Its not the best mega around , but definely not E rank mon.