Before starting, I want to point out that there is already a "Siren" themed skill in Mesmer: https://wiki.guildwars2.com/wiki/Siren's_Call
Also, special thanks to @rdigeri.7935 for helping me with my design choices.
Since I heard this idea in another thread in this subforum, I wanted to design a soft-cc + cheap boons theme with shouts as new utilities.
Main concept is that you get shouts and grant lots of aoe regeneration, swiftness, fury to allies and chill, immobilize, cripple, weaken, blind your foes. It also has transformation, an unseen mechanic in mesmer.
You might want to bring a Siren if your comp has one or more builds that are weak to getting pressured. Siren's biggest strength is that it has taunts and non-damaging conditions. With these utility conditions, it can relieve pressure from high burst classes like thief, revenant and ranger with forcing them to retarget. It can also help against attrition classes with ccing them, cleansing their conditions and declining their cooldowns/kiting with chill and cripple.
This is not a shatter skill, but a transformation like Shroud so you gain extra life bar. The mesmer gains the ability to transform using an energy called "Allure".
Weapon skills are replaced with the following:
1: Damage and apply cripple to nearby foes. (3/4s cast time, 240 radius)
2: Leap to your target, damage and apply chill to them. (600 range leap, 10s cooldown)
3: Taunt your target for 2s and deal damage. (3/4s cast time, 600 range, 20s cooldown, in competitive modes this skill has 0.01 coefficient)
4: Evade and leap away from your target. Apply 1s weakness on your previous location. (Instant cast, 3/4s evade, 25s cooldown)
5: Cleanse conditions from your allies in an area. (ground targeted, 2s cast time, 4 pulses, 35s cooldown)
Siren will get offhand warhorn.
Warhorn 4: Grant fury to nearby allies and remove movement-impairing conditions. Apply 2s weakness and 2s blind to 3 nearby foes. (360 range, Instant cast, 25s cooldown)
Warhorn 5: Create an illusion that grants swiftness to nearby allies and cripples nearby foes. (25s cooldown)
F1: Shatter. Destroy all your clones, damaging and crippling nearby foes. The shatter effect also occurs at your location. (Less damage compared to Mind Wrack)
F2: Shatter. Destroy all your clones, confusing and blinding nearby foes. The shatter effect also occurs at your location. (Shorter confusion duration than Cry of Frustration)
F3: Shatter. Destroy all your clones, dazing and chilling their targets. The shatter effect also occurs at your location. (Shorter daze duration than Diversion)
F4: Shatter. Gain distortion, apply taunt (scaling with amount of clones you shattered) to nearby foes (260) and destroy all your clones. The shatter effect occurs at your location. (Basically just 1 seconds of distort even with 3 clones)
They have the same cooldown (if not 2-3 seconds higher) as core shatters.
They are obviously shouts. They aren't "meaningful" words like usual shouts are. They are mostly loud cries.
Unless stated otherwise, they affect 5 allies and/or 5 foes.
Healing skill: Heal yourself (5k baseline) and gain allure for every nearby foe. If your allure is full after using this skill, remove 2 conditions. 480 range, 30s cd, 1s cast time.
Utility 1: Damage and apply 2s immobilize to nearby foes. Grant swiftness and regeneration to your allies. 360 range, 28s cooldown, 1/4s cast time.
Utility 2: Taunt nearby foes for 2.5s and gain regeneration. Gain 15% allure for every affected foe. 360 range, 30s cooldown, 1/2s cast time.
Utility 3: Break stun, gain vigor and apply 3 vulnerability to nearby foes. Unblockable. Your illusions gain 2s quickness. 360 range, 35s cooldown, instant cast.
Utility 4: Chill nearby foes for 3 seconds and your next 4 attacks apply 1 confusion for 3 seconds. 360 range, 28s cooldown, 1/4s cast time.
Elite skill: For a duration (3s), pull nearby foes to yourself. This skill can affect the same foe every 1s. (channeled skill, 480 range, 90s cd)
Top traits enhance your conditions and your damage.
Middle traits enhance your warhorn, shouts and allure gain.
Bottom traits enhance your taunts.
Adept Minor: You can now use offhand warhorn.
Adept Top: Cripple you apply lasts 33% longer. Chill you apply lasts 15% longer. Immobilize you apply lasts 10% longer.
Adept Middle: Your warhorn skills have 20% reduced cooldown, cleanse 1 condition from yourself and apply regeneration to nearby allies. Regeneration you apply is 15% stronger.
Adept Bottom: Taunts you apply now pulse blindness every second. Taunting a foe grants you 5s fury.
Master Minor: You gain 5% allure for every clone you shatter. This effect counts the mesmer as a clone.
Master Top: You deal 5% more damage to foes for every movement-impairing condition they have. You take 7% less damage from foes with at least one movement-impairing condition.
Master Middle: Your shouts now have 15% less cooldown. Gain 15% allure for every foe affected by your shouts.
Master Bottom: Taunting a foe torments them (2 stacks for 3 seconds, 15s icd). Taunts you apply last 25% longer.
Grandmaster Minor: Your shatters grant swiftness to your clones. When you summon a phantasm, your target is immobilized for 1s.
Grandmaster Top: When you apply immobilize, grant allies near you and your target might, fury and swiftness.
Grandmaster Middle: Your maximum allure cap is increased by 25%. You gain 5% allure every time you apply a movement-impairing condition.
Grandmaster Bottom: Taunting or pulling a foe deals damage (scales by power). Gain 5% allure every time you taunt a foe.
Example bunker build
Sword/Warhorn + Staff
Healing Shout + Blink (or Signet of Illusions) + Utility 2 + Utility 3 + Elite Shout
Paladin amulet, traveler rune (or aristocracy rune)
Inspiration: Bottom, Middle, Middle
Chaos: Bottom, Bottom, Bottom
Siren: Middle, Middle, Middle
Example condition build
Scepter/Pistol + Staff
Healing Shout + Blink + Utility 3 + Utility 4 + Elite Shout
Carrion amulet, aristocracy rune (or traveler rune)
Illusions: Top, Bottom, Middle
Dueling: Bottom, Top, Middle
Siren: Bottom, Middle (maybe Bottom), Middle
Example power build
Sword/Torch + Greatsword
Healing Shout + Blink + Utility 2 + Utility 1 + Elite Shout
Marauder amulet, traveler or scholar rune
Domination: Top, Top, Bottom
Dueling: Top, Bottom, Bottom
Siren: Top, Top, Bottom