Adrenaline Bar

right|300px
The Adrenaline Bar is part of the Player Tab, and is used at different levels for a multitude of abilities, of course, allowing it to charge up. 
Each ability, (at different levels) has two requirements before the bar fully activates. You can choose one ability at a time, and every few levels you have the option of another ability.
===Level 8: Twist of Fate===
Requires: 25 Hits dealt, 3 Minute Cooldown
This does a twisting slash that always hits and has a high critical rate.
===Level 17: Chain Breaker===
Requires: 50 Hits dealt, 2:15 Minute Cooldown
This hits your opponent for a fair amount of damage, plus reinforcing a random status buff.
===Level 34: Wound Regeneration===
Requires: 25 Hits dealt, 5 minute cooldown
This restores 25% of your health.
===Level 51: Bufftastrophe===
Requires: 50 Hits dealt, 2 minute cooldown
This hits the opponent with a status condition, out of Burn, Shock, Freeze, Daze, and Sleep.
===Level 68: 5-Hit Blast===
Requires: 25 Hits dealt, 5 minute cooldown
This hits the opponent 5 times with your current weapon, at the cost of 10 seconds of having your stats lowered.
===Level 77: Miracle Force===
Requires: 50 Hits dealt, 5 minute cooldown
A shield of aura blocks one attack, even fatal.
===Level 85: God's Blessing===
Requires: 75 Hits dealt, 10 Minute Cooldown
You absorb the power of a fighting god, dealing 10x the damage in one strike, which will almost never miss.
===Level 92: Full Restore===
Requires: 50 Hits dealt, 5 Minute Cooldown
Prayers of healing heal all your wounds, and restore you to full health, mana, and rid of status effects.
===Level 100: Maelstrom of Fates===
Requires: 100 Hits dealt, 10 Minute cooldown
A swirling maelstrom comes around you for 1 minute, boosting your damage stat by 500%. The ultimate PVP weapon.
===Changing Your Ability===
Even though you can have only one ability at a time, you don't have to have the same one. Right click the Adrenaline Bar and select Change Ability to change it. Note that however, you cannot change it again for one hour.