Reduces the rage cost of your Execute ability by X.
Improved Execute reduces the rage cost of the Execute skill. It allows for more Executes during a fight where mobs have enough Health to take more than one as well as increasing the maximum damage since the extra Rage will be converted into damage.
Rage cost reduction
Improved execute greatly lowers the cost of one of the warrior's most devastating skills, but it should be noted that around this area in the fury tree, there are other talents which are equally great. In PvP situations, fury/dual wielders may safely ignore this and get a better talent such as Improved Berserker Rage, however for 2handers who use rage-cost heavy skills such as mortal strike and whirlwind, a lower cost Execute will greatly increase their chances of killing an opponent before he can get back up on
his feet with a heal.
A lot can happen while waiting for more rage from damage or another swing just to execute especially with slow weapons (especially against healer types, who won't give you any damage-rage while healing and are VERY likely to heal at 20%).