We all know that if you break off from a battle and escape to another room/cavern/area to rest up and heal and then return to the battle, your opponents will have healed and re-memorised their spells (i.e. the same amount of time passes for your opponents as well).
However in my current battle with Kangaxx I've found that this is not the case (whether intentional or a bug, I don't know).
My solo Mage went to do battle with Kangaxx and summoned a Planatar to help. The Planatar killed Kangaxx in Lich form but turned against my Mage when the Demi-Lich appeared so my Mage scarpered and went to rest up so that he could come back and summon another Planatar.
When returning, the original Planatar had disappeared (expected) but when my Mage tried to summon another Planatar the message came up "You cannot summon another creature at this time" (or words to that effect). Puzzled, I moved my Mage back up to the ground floor and tried to summon a Planatar there - which worked.
Just to make absolutely sure I went away and rested my Mage for 24 hours, went back and tried again to summon a Planatar in Kangaxx's tomb - to no avail, I got the same message.
So it seems that time stops when I leave the tomb and, however long I spend away, when I return to the tomb it is still the same day as when I left.
Can anyone shed some light on this?