I believe this effect is caused by the DoT meant to make sure the turrets live 3 secs but not sure.
Match ID: 28720994
I have replicated this in sandbox if you place down an enemy turret and then shoot it until it is dead, like 25% of the time it gives souls and spawns an orb
Match ID: 28720994
I have replicated this in sandbox if you place down an enemy turret and then shoot it until it is dead, like 25% of the time it gives souls and spawns an orb