I already noticed this bug once when in Blown to Bits. A summoned Ghaele, fully buffed with blur, stoneskin, protection of elements, etc. go havok on the mobs and teleport between them every second, thus producing a hugh lag:


The lag itself seem to be produced through the constant re-apply of the buffs and on the image you can see the fire and electric tubes arround the ghaele at different location while it teleport. It more or less freeze my system while doing so and only stopped after the enemy was dead. I did already bug report it but I wonder if someone else noticed this too and if this only affect the Ghaele or other summons that can telport as well.