Some summons and monsters are very difficult to use because the collision sizes for them are so large - Earth Elementals and Ice Elementals stand out as two notable examples where their collision space is much larger than the physical models. I have witnessed 2 ice elementals on either side of an enemy being unable to actually attack the enemy because of this. I believe that this is primarily due to the CREPERSPACE values in Appearances.2da
QuoteTechnically, the NWN engine avoids collisions using two parameters in appearance.2da - CREPERSPACE and PERSPACE. Bioware has stated that PERSPACE (Personal Space) is used to prevent wall collisions, whereas CREPERSPACE (Creature Personal Space) is used to prevent creature collisions. This is why horses clip into walls, but can't pass between two guards unless the gap is really large. The actual implementation is more complicated than that, as illustrated by the discussion in this section. It seems that CREPERSPACE is used for spawning, but EffectCutsceneGhost by-passes collision checking, and no further check is made until the creature tries to move. Evidently, there are also implications for combat; CREPERSPACE seems to be used between blows to keep the opponents apart, but PERSPACE governs the distance at which blows are struck, to allow the opponents get close enough for the kill.
The CREPERSPACE for earth elementals and the crystal golems is 1.7 - for reference, a human is 0.5 and a dragon is 2.0. I think if we reduce this value it will make them more viable as summons and monsters. It is a 2da change so the impact to the haks would be small, since all the Q! haks are distributed in a separate file.
I already have with recent update. Not all and not crystal golem in particular, but when I next apply updates, I'll check that as well, but earth elementals were among updated ones already.
Just write very short list of creatures or appearances that still have obviously too big collision and personal space, and I'll check them when I have the time for next edit.
The ice elementals are still very big and unwieldy. I believe these guys use the Diamond Golem models.
The lines in Appearances.2da for the golems are:
926 "Golem: Ruby 2"
927 "Golem: Emerald 2"
928 "Golem: Emerald 3"
929 "Golem: Diamond 2"
930 "Golem: Amethyst"
931 "Golem: Sapphire"
932 "Golem: Topaz"
Many of the druid wildshapes have a similiar issue if it's possible to reduce their collision. The slug and frog are the greatest offenders unable to fit through any doors.