Lightning Psychological: One of the best builds! Pretty simple. Follow the skill tree and you should kill them. HAVE CHARGED BLOOD MAXED!
Shadow Psycho: Ugh... This is a really complicated skill. Basically, use Epiphany, then Dark Infusion (on enemy) until Epiphany CD is done. Repeat. Have insecurity also.
Hot Hydro: Regulate, Impair, Decimate, Wreck, Wreck. HAVE LASTING PAIN MAXED!
Cold Hydro: This is a really fun build to play with. Use any of the "shatter skills". Shatter skills are basically skills that require no focus and damages 200% instinct. THEN PWN WITH SHATTER! Remember to have the ice piercing passive maxed.
I hope that helped!
Quick beginner guide:
Poison Biological: Use Corrosion as an early move, then use Infect three times. You should have Corrosion, Infect, Acidic Blood, and Toxicant Form all maxed out!
Physical Bio: This is the most complicated build for me. Use Agile Exposure first. Animalism is a joke DO NOT USE IT UNLESS YOU HAVE A TON OF VITALITY. Vicious Strike is also good when maxed out. You should have predator and savagery. You should also have Break. It is IMPORTANT.
Speed Biological: Easy to use. Makes One hit kills in 3 moves! Use Sharp senses, then Shadow Blend, then Slash! OWNAGE! Have savagery and evolution passives.
Overdrive is a good passive skill.
Use Terrify first so you don't die. Using Free Will is also OK. Use Epiphany > Insecure > Dark Infusion X3 > Implosion!