I dislike giving momentum to anything non gravity without at least costing gravity quanta to activate. After life, gravity is probably the weakest element.
Rhino: I like it, gives some PC to life and a nice mid-range attacker
Army Ant: Ability is like swarm, maybe you could phrase it similar? Meh, okay but not as good as scarabs
Mantis: How does it work with shields that block damage completely? (does the card gain infinite attack or what?) its okay, but see above.
Entice/Rage: to different, split them into two different cards. not really something i would use personally, light/life duo well so might as well use blessing and see above about momentum
Malignant: Made me think itd have to do with malignant cells, might want a name change. otherwise its a good idea, the unupped is much better though unless youre playing voodoo (but then you could use pests, eh) also, this card hardly fits the set O_o
My 2