This only really works on single player.
Extend a glute, contract the leg and knee on that side and extend the ankle on that side. Bend the lumbar LEFT if its the left leg and RIGHT if its the right leg.
Press space once.
Extend the knee.

Not bad. I dismembered his leg and got like 14000 points on normal settings.

Another opener!
This is basically a noobclap but UBER powerful.
Just extend both ankles and contract both pecs, and click both hands to grab. BOOM! Instant 90k.

These aren't openers. Openers are set moves you have for certain mods on multiplayer.
No offense though but these are pretty damn nooby.

GOOD ONE LOL

Meh, oh well, you can use them as starting moves anyway, and 1 of them gets you 90k damage, which is pretty hard to get in about 10 to 20 frames. Whats more both of them cause no damage to you, I think... meh, but they might still be nooby, but I am a noob so you can't complain.