This isn't really a bug, more of a request for a rework of an existing summons.
The Doom Knight currently casts the following spells, each time he is summoned: Power Word, Stun; See Invisiblity, Dispel Magic, See Invisiblity, Dispel Magic and then Fireball. Generally its in that order. The problem I see is .. why would he need to cast see invisiblity on himself twice? Basically it works like this .. he stuns a creature .. then dispels his own spell. Kinda silly. I would rather he only had 1 see invisibility and 1 dispell magic. As it is, it takes forever to get him to finally engage in combat.
Just thought I would mention this as an observation.