I'm okay with Psychological, but Hydraulic was always better off for me. You should've made the title different, it makes it sound like you are asking for a definitive best-class :P.
i played the hydraulic class havent played others. Really i have to say whatever you like is the best class for you. So if you want the psychological class cool. whatever class works best for you is the best one. i prefer hydraulic but for you that may not work. So experiment to find what works best for you. Good luck!
Like i said above psychological always works best for me and I am really good with it. I have beaten the game with all classes, but I am beast with the electric build in psychological. The Biological build is really good for players who don't really like complicated build and it's probably the most straightforward. Hydraulic is complex, asking you to combine strength and instinct. The attacks in the beginning are extremely weak, and not many items provide ice piercing, but if built right, it can be devastating in attack and defense. Psychological is also a complex tree, asking mostly for instinct, but if built right, in my opinion, is the most destructive in the game.
Jagajaga, that's fine. But, do you know the massive-damage-combo for the biological? I suggest you test this out, just to see how awesome it is. Combo: Toxicant form, Shadow Blend, Agile exposure, Withdrawal.
Available at level 10 and works on just about everything except the **** hydra.
I tried them all and my favorite is by far Psychological. It's a little rough to go full instinct at the beginning, but it pays in the end; all the last bosses bowed to me in but a few turns. I go for the dark build, with everything that boosts instinct, then there's a particular wheel setting to maximize damage. When done right, Epiphany can easily deal over 10000 damage per turn, even for a level 22-23. I'd have to check my game again to tell you the exact set up of my action wheel and my skills.
spartandestroyer, yes it works on Nostalgia, but you might have to drop his HP to about 2/3 first, I don't remember if you would be able to amass speed required for full 40k strike. And about Omen, no, this combo requires careful preparation while Omen gives only a window when to deal damage and threatens with one-hit kill.
Abhi, Shattering Beast is a damage build while the best ability of a hydro is healing. And Shatter requires you to move faster than Roald or Veradux so they could take advantage of first turn Shatter debuff, but hydros have the least speed of all the Sonnys.
FallenSky, I wonder what do you do to land a 10k/turn Epiphany. Double sacrifice and Insecurity? Still not enough IMHO...
i would hate to see someone abuse the 2 classes glitch to get a shadow form into a shattering beast! 8/ now that i said that it seems like a pretty good idea...