Dino

Chaosium's Basic Role Playing is pretty damn easy to learn. Especially the percentage based skill system. The quick-start rules are free: *** clicky ***

Here's an MMA writeup I did using custom martial arts maneuvers:
 
Cost    
    Mixed Martial Arts
4    1)  Choke Hold:  1/2 Phase, -2 OCV, +0 DCV, Grab One Limb; 2d6 NND
5    2)  Defensive Block:  1/2 Phase, +1 OCV, +3 DCV, Block, Abort
3    3)  Double Leg Takedown:  1/2 Phase, +2 OCV, -1 DCV, 3d6 Strike, Target Falls
5    4)  Escaping Throw:  1/2 Phase, +0 OCV, +0 DCV,  25 STR , to Escape, Target Falls
3    5)  Grappling:  1/2 Phase, -1 OCV, -1 DCV, Grab Two Limbs, 20 STR for holding on
5    6)  Ground N' Pound:  1/2 Phase, +0 OCV, -2 DCV,  6d6, Strike, Must Follow Takedown
5    7)  Low Kick/Knee Strike:  1/2 Phase, +1 OCV, -2 DCV, 6d6 Strike
4   ? Punch/Elbow Strike:  1/2 Phase, +2 OCV, +0 DCV, 4d6 Strike
4    9)  Reversal:  var Phase, -1 OCV, -2 DCV, 25 STR to Escape; Grab Two Limbs
5    10) Roundhouse/Spin Kick:  1/2 Phase, -2 OCV, +1 DCV, 6d6 Strike
3    11) Sacrifice Throw:  1/2 Phase, +2 OCV, +1 DCV, 2d6 Strike; You Fall, Target Falls
4    12) The Sprawl:  1/2 Phase, +0 OCV, +0 DCV,  25 STR , to resist Throws, Block, Abort
 
MMA.hdp

Costs in Gurps are based on hard they are to get, costs in Hero are generally how effective they are in combat.  #grossoversimplification

5th Edition: make sure that you have Star Hero selected as a source.
 
6th Edition: Assign a custom Adder to the Skill, set the name to whatever category you want and set the cost to 2 points.  The skill will switch from 3/2 to Adder/category based.

Immortality Syndrome (Champions Powers pp 379-380)
 
Extra Body: Only to prevent death (-2)

An impairing wound is when you take ½ or greater of your body before or after the multiplier.  Disabling is if you took full body before or after the multiplier. This rule is the same in 6th edition as it was in earlier editions.  It is also suggested that unimportant thugs and NPCs should be considered dead if they receive a disabling wound for faster game play. 
 
I would consider a disabling wound to the head to have decapitated an unimportant NPC.  For a PC or important NPC they are only decapitated if they roll a 6 on the disabling chart and fail the CON roll.  If any character is outright killed by a head shot they could be considered decapitated. 

Crow bar: + 10 STR only for lifting/prying
 
Did you know Fire Axes are kept duller than wood axes because you use them to smash down doors more than cut through them?