If it's off GCD without a CD it'd just be macro'd into every ability. I think it's best the ability just be passively applied through certain abilities if it's going to exist in a permanent debuff state at all (which also helps bring up players who don't macro anything). I think in a passive debuff state it's best if it interact with the kit in some way, rather than just being a flat damage increase. But I think a minor/major CD (30sec/1m/2m) is probably a better spot for it if it is just a damage debuff. I think they'll be moving away from raid-wide debuffs in the future. I can't see raid-wide debuffs lasting going forward as reception to raid-wide debuffs and raid-wide buffs returning has been largely negative (granted, probably a result of how powerful they were, if they were more minor it probably wouldn't have been much of an issue). If the ability is just a way to track targets it becomes virtually useless for most content and just becomes button bloat, but admittedly this a very inoffensive iteration. I don't think it's much of a debate that on GCD and spamable while necessary for the damage debuff now feels terrible to have to reapply, and in that interaction it adds unnecessary ramp-up and slows burst when small things need to die asap, with pre-cast on pulls basically being the only fun interaction with it if any. If it was only usable before you were in combat with a target, maybe that's one space for it but it loses a lot of flavor when new spawns make their way into fights and it can't be used that way as new adds commonly will be in combat with everything automatically (same reason rogues can't re-stealth for those mobs, in addition to still being detected by boss even if they're clear off in another dimension out of sight but that's not here nor there really). Honestly I'd probably rather see it removed entirely as I've never liked it. But if it has to stay the less cumbersome and annoying it is, the better imo.