You need to pull Kymar. He opens with his a3, resetting everyone's cooldowns, even though no one has any skills on cooldown

Sounds like I need to add him to my team xD

Oh! Or Ramantu:

If the target has stoneskin or block debuffs, he'll open with his 4-debuff a2, and won't use his strip buffs a3 until block debuffs wears off on its own

Sadly, this is because his A3 also has a TM boost, and that makes it a high-priority move :/

Similarly for Kalvalax, the A1 increases debuff duration, which is higher-priority than simply attacking, which is all the A2 and A3 do - despite, of course, those moves being much more useful.

And, for Nobel, the reason is because the A2 places continuous heal buffs on your team - again, higher priority than just doing "damage", which is what the A3 does.

I suggested something a *long* time ago to help for this, though it wouldn't really solve this specific problem - https://forum.plarium.com/en/raid-shadow-legends/674_game-discussion/615811_give-us-a-few-combat-ai-options/

I will forever be a big fan of dumping long CD abilities into an enemy with 10 hp left.