Button combo

A button combo is a sequence of buttons that, when pressed in order, results in the execution of an exploit. Typical button combos take advantage of unforeseen attributes of certain actions. Some actions, such as meleeing, can disrupt animations for firing and reloading weapons, performing melees, etc. By chaining these and other actions, players can perform special tricks, such as automatic Plasma Grenade sticks and instant close-range kills. However, many players disapprove of such "cheap" exploitations, and Bungie has declared these combos all as cheating and therefore banworthy:Bungie.net: Halo 2 Forum: Why button-glitching isn't cheating: 
==Halo 2==
===X===
The X button can cancel the timers of animations, such as melee or grenades (off-host), enabling you to fire or melee sooner than you would normally.
===Y===
The Y button can cancel reloading, cancel melee animations, and, when used in a quick double sequence, it can enable you to open fire again sooner after reloading.
===B===
The B button can cancel the reload timer by meleeing and pressing X afterward. The melee's lunge can also be used to swing at your opponent, after which you can snipe someone no-scoped or stick people with a plasma grenade.
===L===
The L button can be used to reload. After you have thrown a grenade, press X. You will automatically reload, but you can keep shooting while you reload (off-host).
===Overheat===
Overheated plasma weapons have extra abilities. After a weapon overheats, it will reset the timers for shooting, meleeing and grenading; this can be used to get quick sessions of double grenades.
==Halo 3==
Some players discovered a "BXB-style" glitch that allowed them to melee twice in quick succession. Bungie posted on the February 8, 2008 Weekly Update that they had fixed the glitch and would release the fix in the first TU on February 19, 2008.
==Sources==
 
Category:Halo 2 Glitches