How about adding different environmental stages?

e.g.
The pool - You're under water, so ranged weapons don't work (only swords, stomp, charge, grapple, maybe missiles/torpedoes)
Ice-Land - You never overheat, heat weapons do half damage
Desert - Mechs slowly overheat over time -or- strt with 50% heat
Storm - Some electrical storm messes up energy levels.
Minefield - You move, you explode (just kidding on this one)
Mini-field - Much smaller arena to fight it
Warp-areana - You go off the left of the screen, you re-appear on the right
etc

I liked it, why "joke"? You can make it "knockback has a chance to activate mine explosions". So a knockback weapon can throw you to a mine and deal extra damage.

I disliked this.

I only use heat weapons, this will ruin my game and it is totally random

^HELL YEA

Because every weapon has knockback now, so whoever goes first would get a huge advantage. If the knockback was put back to its previous level, it could work



That's the point, to make things a bit more random, so no matter how good you build your mech, there will be stages you are bad at.
On the flip side, there would also be levels that enhance your mech design.
e.g. if you go up against a mech 5 times you level on the desert stage, you could win, because the desert heat enhances you heat attacks.

Another idea

Zero-G/Space - Knockback and jumping distances are double (maybe walking distance too)

Anyone else have any ideas for stages?