1) Even if it's killed mid charge a Killshots damage will still go through most of the time resulting in you occasionally getting bodied by a flaming wheel.
2) Lancers can jump to some really evil places on certain maps that put them out of the targeting range of most weapons. Combined with Javs this can let them hammer enemies in complete safety.
3) The Panthers shield blocks bullets the instant it is deployed not when the animation shows it activated and it lingers for a few seconds after the animation collapses (say if a Guardian takes it down) so you can use it on reaction to block things and you need to wait a second or two in order to shoot through where an enemy shield was.
4) If you are under 50% HP you can walk up to MD AIs and they will activate their heal. They won't stick around to heal you up, but you can follow them to recover some HP.
5) The Ares' shield does not block a Killshot charge if it gets close enough before activating it.
6) If you are using an Ares with a deployed shield and someone shoots Javs at you walk backwards! It makes it more likely they'll impact your shield and not the mech. If you walk forwards the barrage will almost certainly hit you in the back.
7) Do not run towards mechs shooting you with explosives! (RPGs, Disks, MRs) The hits will register as hitting your back dealing massive damage even if they are striking your front as you will be walking through the explosion before it registers the hit. This can even happen at a walk if the latency is bad.
8) If you know what direction a Jav launch is coming from you can quickly deploy a panthers shield and stand just on the opposite side to block it. If you're not sure, deploy the shield and stand perfectly in the middle. Chances are you'll stop at least a few of the hits.
9) The Guardian's pulse can affect enemies with respawn invincibility making it a great spawn camper.
10) Javs can be launched at some surprisingly weird angles to hit targets around corners or under cover.
11) The various "pulse" powers all go through walls.
12) The "pulse" powers all reach 30m. The Redox and Zephyr hit a 30m in a 360 centered on the mech. The Guardian goes 30m in a wedge in front of it.
13) You can still shoot Shadows when they are cloaked provided your weapon doesn't need a lock on. (It's surprising how often I see people just staring at them assuming they're invulnerable.)
14) The Prototype mechs aren't that good. They have uses, but they're all very specialized with rather glaring downsides compared to more common mechs.
15) The disk launchers don't need a lock on to shoot, they just don't have the homing without it.
16) Shooting Javs from higher ground then the target will generally result in them connecting with it's back for more damage. Aiming at mechs moving toward you can result in the same on even ground especially if they are quick or running.