Yea. . calling it an animation lock is inaccurate, this is a latency issue. It relates to the Send Receive.

See when you Send out Bio, it's shows on your side that Bio is active but if you use Bane right after and send that as it receives the info on the Bane it still hasn't received/refreshed the info to acknowledge the Bio on the mob and thus doesn't AOE the Bio.

They could just change it where Bane comes with Bio on it, which could work since it would solve the issue of using both in rapid fire.

It wouldn't make Bio useless since it could still be used on single targets and Contagion and by itself, it's not like people would just throw bane out to only AOE Bio, so there is nothing lost if they just have it where Bio is a part of the Bane effect, maybe just have it where Bane is no long off global Cooldown and suffers the same cooldown as if you used Bio.

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So basically change Bane to have "Spreads Bio/Bio II/Miasma"

"If Bio is not present on target spreads Bio to all in AOE Radius" (If this occurs player is given a cooldown as if they had cast Bio)