Useful party skill per class and class combination

Here is a list of all useful skills/passive skills to consider while going in a party. Almost every class and class combo brings a buff, long or short, to the group to help with either damage dealt, damage received, and aggro generated.
Other classes bring utility skills needed for certain boss mechanics.
Please bear in mind that this list show all skills that will benefits a party. All personnal buffs are not on this list
== Champions ==
Class 	Icon	Skill Name 	Level	Cost 	Cast Time	Cooldown 	Range 	Skill Effect 	Upgrade
Champion 	 	 	65 	50% HP 	1 second 	5 minutes 	Self Circle (R:??) 	Sacrifice 50.0% HP to create a shield that protects your party members for 5.0 seconds. Shield Effect: -50% of damage received. 	Item Set Skills
Champion/Mage 	 	 	30 	17 MP, 1% MP	Instant 	60 seconds	150 	Reduces a party member's Received Physical Damage and Received Magical Damage by 10%..40% Lasts for 10.0 seconds. When this party member is hit during the time of the effect, your current Rune Draw cooldown time will be reduced by 12 seconds. 	+0.6% per level
Champion/Priest	 	Salvation Engraving	30 	30 MP 	Instant 	4 minutes 	 	Reduces the Received Physical Damage and Received Magical Damage of nearby party members by 5.0%..30.0%. Also reduces any aggro, inflicted while in effect, by 5.0%..30.0%. Lasts for 10.0 seconds. (This skill has no effect on the caster.) 	+0.5% and +0.5% per level
Champion/Priest	 	Suicide Advance 	45 	30 MP 	Instant 	5 minutes 	 	Sacrifices the caster's defense to increase the attack of him and his party members. Reduces the caster's Physical Defense and Magical Defense by 5.0%..20.0%. Also increases the Physical Damage and Magical Damage of the caster and nearby party members by 5.0%..20.0%. Lasts for 15.0.	+0.3% and +0.3% per level
Champion/Priest	 	Righteous Explosion	70 	10% MP 	3 seconds	30 seconds	150 	Casting takes 3 seconds and removes all harmful effects from all party members in range. 	
Champion/Rogue 	 	Smoke Diffusion 	60 	50% HP 	Instant 	5 minutes 	Self Circle (R: 200)	Consumes half of caster's HP and lets all party members in range disappear for 5.0 seconds. The caster is unable to move for 12.0 seconds.
(Can only be used in a Shield Form state.) 	
== Druids ==
Class 	Icon	Skill Name 	Level	Cost 	Cast Time	Cooldown 	Range	Skill Effect 	Upgrade
Druid General	 	Antidote (+) 	4 	150 MP 	Instant 	10 seconds	200 	Cleanses your target from poison. 	
Druid General	 	Savage Blessing 	8 	35 MP 	Instant 	 	180 	Increases target's Physical Attack Accuracy and Magical Accuracy by 1.0% + 20.0 for 1800.0 seconds. 	+0.1% per level
Druid 	 	Body Vitalization 	36 	100 MP 	Instant 	2 minutes 	200 	Increases target's Physical Attack Speed by 2.0% for 12.0 seconds. 	+0.26% per level
Druid 	 	Concentration Prayer 	28 	35 MP 	Instant 	 	 	Sends a prayer to Mother Nature, beseeching her to increase all of your party members' Wisdom by (current Wisdom + 10.0) x 1.0% + 10.0 for 600.0 seconds.	+1 per level
Druid 	 	Purify 	2 	150 MP 	Instant 	10 seconds	200 	Cleanses your target from curses. 	
Druid/Rogue 	 	Speed Catalysis 	20 	15 energy	Instant 	5 minutes 	 	Temporarily raises the physical attack and casting speed of party members within a range of 150 by 20.0% for 20.0 seconds. 	
Druid/Warden 	 	Mysterious Grace 	35 	100 MP 	Instant 	 	 	Increases your and your party members' Magical Damage by (current Magical Damage + 15.0) x 1.0% + 15.0 for 1800.0 seconds. 	
Druid/Warrior	 	Awakening of the Wild	35 	30 MP 	Instant 	 	 	Increases your and your party members' Physical Attack Power by (current Physical Attack Power + 40.0) x 1.0% + 40.0 as well as Physical Damage by 25.0, both for 1800.0 seconds.
(This effect cannot co-exist with similar effects.)	+8 and +1 per level
== Knights ==
Class 	Icon	Skill Name 	Level	Cost	Cast Time	Cooldown 	Range	Skill Effect 	Upgrade
Knight	 	Holy Shield 	1 	 	Instant 	5 minutes	 	For 5.0 seconds, every party member within range receives a shield which can block all physical damage. 	
Knight	 	Hall of Dead Heroes	42 	 	Instant 	3 minutes	 	After use, all party members within range will receive the Hall of Dead Heroes effect. Received Physical Damage decreases by 10%, Received Magical Damage decreases by 10%, and Movement Speed increases by 30% for 15 seconds.	
== Mages ==
Class 	Icon	Skill Name	Level	Cost 	Cast Time	Cooldown 	Range	Skill Effect 	Upgrade
Mage 	 	Fire Ward 	24 	120 MP	Instant 	 	 	Increase the party's Fire resistance by 10.0 points for 10 minutes.	+2.0 per level
Mage/Priest	 	Purify 	20 	150 MP	Instant 	10 seconds	200 	Can dispel curses from your target. 	
== Priests ==
Class 	Icon	Skill Name 	Level	Cost 	Cast Time	Cooldown 	Range	Skill Effect 	Upgrade
Priest General	 	Magic Barrier 	12 	120 MP 	Instant 	 	 	For 900.0 seconds, all party members' Magical Defense increases by (6.0%..39%).
The maximum level of this skill is 50. 	+0.65% per level
Priest General	 	Blessed Spring Water 	16 	120 MP 	Instant 	 	 	Increases party's Water resistance by (10..200) points for 900.0 seconds. 	+2.0 per level
Priest 	 	Cleanse 	18 	150 MP 	Instant 	10 seconds	200 	Removes harmful effects from target. 	
Priest/Knight 	 	Devotion Halo 	50 	 	Instant 	 	 	Raises the Wisdom of party members within a radius of 200 by 5.0% and reduces the mana cost of the other party members' skills by 6.0%. 	
Priest/Mage 	 	Angel's Blessing 	25 	100 MP 	Instant 	 	 	The Angel's Blessing grants your party restoration of additional 10.0 MP every 5 seconds. Lasts 600.0 seconds. 	+0.8 per level
Priest/Mage 	 	Windrider Halo 	50 	 	Instant 	 	 	Raises the magical accuracy of party members within a radius of 200 by 6.0% and the master's Heal increases by 5.0%. 	
Priest/Rogue 	 	Shadow Fury 	40 	100 MP 	Instant 	 	 	Increases the whole party's Critical Magical Hit Rate by 20.0 for 900.0 seconds. 	+2.4 per level
Priest/Scout 	 	Embrace of the Water Spirit	15 	100 MP 	Instant 	 	 	Beseeches the Water Spirits for their blessing, and raises your and your party members' Magical Attack Power by (current Magical Attack Power + 20.0) x 1.0% + 20.0 for 900.0 seconds. 	+0.09% and +8 per level
Priest/Scout 	 	Frost Halo 	50 	 	Instant 	 	 	Lowers the Received Magical Damage of party members within a radius of 200 by 10.0%. Also while Frost Halo is in effect, the Critical Magical Hit Chance of Rising Tide increases by 10% and damage caused by Ice Blade increases by 10%. 	
Priest/Warlock	 	 	30 	 	 	 	 	Cleanse can also remove cursed states. 	
Priest/Warlock	 	 	35 	20 focus	Instant 	30 seconds	150 	Blessed by the holy spirit, you are able to pull a friendly target close to you. 	
Priest/Warlock	 	 	60 	20 focus	Instant 	30 seconds	 	Blessed by the holy spirit, you are able to pull friendly targets in a range of 180 close to you. 	
Priest/Warrior	 	Accuracy Halo 	50 	 	Instant 	 	200 	Increases the physical attack accuracy of party members within a radius of 200 by 6.0%. While this effect lasts, the critical hit chance of the master's Ascending Dragon Strike increases with 20% and using Explosion of Fighting Spirit has a chance of inflicting even greater damage.	
== Rogues ==
Class 	Icon	Skill Name 	Level	Cost 	Cast Time	Cooldown	Range	Skill Effect	Upgrade
Rogue/Priest	 	Quickness Aura	15 	30 MP	Instant 	 	 	Your and your party members' dodge rate raises by 2.0% for 900.0 seconds.
The maximum level of this skill is 50.	+0.28% per level
== Warlocks ==
Class 	Icon	Skill Name 	Level	Cost 	Cast Time	Cooldown 	Range 	Skill Effect	Upgrade
Warlock 	 	Sublimation Weave Curse	18 	50 focus 	Instant 	- 	Near Party	Weaves psychic energy around all party members and raises all attributes by 2.0..6.0% for 1800.0 seconds.
The maximum level of this skill is 50.	+0.08% of all attributes per Level
Warlock/Priest	 	 	40 	2 Soul Points	Instant 	- 	Self 	Only usable under the state of .
Caster and friendly party members earn Soul Enlightenment which raises Maximum HP by 10.0..50.0% and Received Healing by 6.0..30.0% for 10.0 seconds.	+0.4 and +0.2 per level
Warlock/Rogue 	 	Liquidation Suffering 	40 	2 Psi 	Instant 	4 seconds	200 	Only usable under the state of Willpower Construct.
Temporarily increases aggro caused by a friendly target by 5.0..30.0% and reduces the aggro caused by the caster and other party members by 5.0..30.0%. Lasts for 10.0 seconds.	+0.25% and +0.25% per level