Dropping this as a concept first. Tell me if it's too stronk or something. Don't mind if the amount of stacks to trigger Stasis is 24 instead of 12, because attack speed and accuracy stacking would make this character insane. Also don't know what suitable cooldowns to put on those two actives.

[hider=Mauve Night Abilities]
LVL 1 – The Clock Starts Ticking
Passive
Instead of doing damage, ranged attacks by Mauve Night inflict an 8.3% Slow over the target, a debuff that effects movement speed, attack speed, and casting speed. This slow stacks up to twelve times, until it reaches 100%, in which case the target is completely stopped, afflicted by the ‘Stasis’ debuff for two minutes. Stasis cannot be removed by status-removing abilities. 

LVL 2 – Good Night
Active
With a snap of their fingers, Good Night is activated, instantly killing any player under the effects of Stasis. Their bodies are pummeled by a barrage of invisible impacts, before they explode into fragments of glass. Against Dissolutions, Good Night is a critical strike that ignores resistances, dealing 1200% of Mauve Night’s base damage.

LVL 3 – Thirteenth Hour
Active
With the chime of an otherworldly clock tower, Thirteenth Hour is activated, simultaneously dropping Mauve Night’s HP to 1% and tripling their movement speed and attack speed, as well as granting them one extra Action for the remainder of the Round. At the end of the Round, the debuff ‘Temporal Judgement’ is placed upon Mauve Night, setting their current HP as their maximum HP for 5 minutes.

[/hider]