Rank 11 Swarm of Decay Cast: Swarm of Decay VI *Swarm of Decay VI, when activated, summons 3 level 82 stationary skeletal archers that will cast Dark Arrow VII on their target every 3 seconds for up to 60 seconds. Reduces the reuse time of this ability by 3 minutes. Rank 12 Swarm of Decay *Swarm of Decay VII, when activated, summons 3 level 73 stationary skeletal archers that will cast Dark Arrow II on their target every 3 seconds for up to 60 seconds. Rank 13 Swarm of Decay *Swarm of Decay VIII, when activated, summons 3 level 74 stationary skeletal archers that will cast Dark Arrow III on their target every 3 seconds for up to 60 seconds. In other words, Rank 12 summons inferior summons compared to the rank 11 version. I could only afford 2 ranks of the skill, so can't check rank 14.
I have it at rank 11 and see that rank 12 will make it worse, so not buying any more AAs in it until fixed.