The field testing questline, where it turns you into an icy look. Would like that for what ever your wearing, even without the helm, you get a permanent ice appearance. Looks cool! Pardon the pun!
By permanent, i assume you mean a buff that can be turned on and off. Exactly like the wizards frozen effect? Otherwise if you mean permanent as in, it's always on you, then not only no, but heck no. People would do the quest without realizing it's long term effects. That being said, i wouldn't mind a modernized visages by quest/zone. Ice for everfrost quest. Or from Velius. Fire effect from lavastorm, newer one at that, the wizard one is ok, but that doesn't look like fire what so ever. Very outdated, and i know the devs can do better. Maybe also from Jarsath, a nice veeshan peek quest. A nature effect from feerrott or kunzar, simply have leaves and flowers grow on you. Void from Moors. And djinn sparkles from Sinking sands. I'd like to see quest that would grant effects from any of these zones. A nice hard epic x2/x4 quest line, all for a fluff spell. I'd be all over that. And maybe.. rivervale, have bubbles come from your head.. drunk little halflings. ^_^
