I will focus more on the Zero in MMX4 since it is when he got his own storyline and everything.

I'll start off with Zero's abilities:
Raijingeki - electrical ground attack.
Tenkuuha - His "violet" saber which can destroy any energy projectiles
Ryuenjin - Upward Fire slash, and it can connect to any move Zero has in Air.
Shippuuga - An attack performed while dashing, very destructive.
Hyoretsuzan - Diving Ice attack.
Rakuhouha - Knee down on the ground sending nine energy blasts to the sides and upward at all angles. Invincible as the attack has initiated.

3 slash combo
While in air, Zero can perform another jump and dash. Also, the spinning Kuuenzan attack is avaliable in air, cutting anything that apporaches.

(I'll...be in school. Got to go now.)