The official GemStone IV encyclopedia.
Chunks of ice appear to be held together by strands of organic material to form the rough outline of a bipedal creature. The chunks have no specific shape, and some are larger than others without direct relation to placement on glacial morph. Often the glacial morph draws in on itself, the chunks rearranging and reattaching to form a considerably different shape, and it seems to be able to change color at will to match its surroundings. The glacial morph peers out from two malevolent eyes set deeply in a 'head' of ice. Strangely, the head does not always appear to be on top of the torso.
Glacial Morphs are fairly straightforward creatures, with a few exceptions. Some weapons will not hurt them, and will just bounce off. (Specifically, this applies to all weapons which do not possess fire, steam, or plasma flares. Fire flaring weapons will work, regardless of the origins of the flares.) Given their icy nature, they are weak to fire as well.
Glacial Morphs also have the ability to remove the spell Elemental Blade (411) from your weapon when you hit them:
You fire a wooden arrow at a glacial morph!
AS: +352 vs DS: +237 with AvD: +23 + d100 roll: +86 = +224
... and hit for 68 points of damage!
The glacial morph sucks the elemental energies out of your wooden arrow.
The wooden arrow ricochets away from a glacial morph, landing nearby.
Roundtime: 4 sec.
For this reason it can be very frustrating for an archer without access to the Elemental Blade (411) spell.
They are also immune to taking injuries in certain areas of their bodies. They will still take health damage, but will not incur a wound. Aside from this, they are basically standard melee fighters with a high AS who do not pose much of a threat. They do have one maneuver, however, they rarely use it and it is not that dangerous. They will lash out at you with an icy tendril, and, if successful, will cause a minor, with no damage, stun, RT or knockdown.
Glacial Morphs, like the animated slush, drop no gems, but will regularly drop drams, pinches, and handfuls of gold dust.