What do you do when you've cornered the bad guy who has just made sure that the person you're protecting will probably be targeted for life, he invokes diplomatic immunity, and he says that even if you kill him, others will take his place? If you're Mamoru, you cut off his arm and leg and then calmly walk away, that's what. See here, here, and here.
And in a later chapter, going up against the same guy (who really doesn't know when to quit), he cuts off Turus' remaining arm, see here. Please note that at the time Mamoru is completely blind, without his sonic sunglasses.
Tate Karito smashes his fist through the driver's window of a car and then pulls the driver out of the window by his FACE.
Haruka taking on a bear. Granted, all she did was dive out of the way and let Mamoru make a bear-kabob out of it, but still. It takes balls of steel to charge at a pissed off grizzly. I'd like to see Dai or Senji do that.
Could we? You know, for the lulz?
In the special chapter 99.5 we see that Jesus has gone through and wiped out several bases- completely by himself. Even Mamoru is impressed, and admits that he would run away from him in one of the later chapters.
Jesus, Aegis, and Mamoru all fighting together
After Edge lets out a rage filled rant and a volley of attacks able to push back Genda and Aegis, he makes the mistake to claim that Haruka is his property and will not let anyone take her. Genda and Aegis both get understandably pissed off at him and both charge forward to deliver a brutal curbstomp on Edge, the end results of which leaves Edge once again down three limbs.
Mamoru frames a repeat assaulter for a terrorist attack. It's as awesome as it sounds.