If you're looking for high direct damage with no cooldown, Mind Flay is supposed to be that spell.

如果你想要无冷却的高伤害法术，精神鞭笞应该就是你要找的东西。

youdao

Glyph of Mind Flay now Increases the damage done by your Mind Flay spell by 10% when your target is afflicted with Shadow Word: Pain.

精神鞭笞雕文：当你的目标受到暗言术：痛效果影响时，可以增加精神鞭笞造成的伤害10%。

youdao

Mind Flay - Fixed a bug with targeting where you would not deal damage if not facing the target while channeling.

修正了一个当你在引导时没有面对目标则不会造成伤害的BUG。

youdao