The official GemStone IV encyclopedia.
As magnificent as any living horse, this shadow steed stares beyond you with glowing red eyes. Its matte black coat provides a sharp contrast to its shining silvery tail and mane. The shadow steed paws the ground restlessly with its front hooves as it swishes its tail, flickering into and out of the shadows.
Shadow steeds are found in the same place as shadow mares, so it is necessary to consider both of them. Shadow mares can notably be knocked down with Elemental Wave (410), but shadow steeds are immune to the effects of the spell. Thus, while the steeds are capable of knocking you down with that spell, you cannot use it to give yourself breathing space on RT from standing back up. While the shadow mares will stun easily, the same is not true of the steeds.
Both shadow steeds and mares have the ability to disappear, effectively negating your attack on them. However, while they are "invisible", they cannot be sensed with Presence (402). They are also non-corporeal undead, so they are not vulnerable to critical hits. Steeds are stun resistant even under Phase (704).
- Shadow steeds can shake off stuns.
Shadow steeds have a chance to turn invisible after an attack or maneuver is made against it:
Just as you move to strike, the shadow steed fades into the shadows!
Shadow steeds have an AS boosting maneuver, which allows their Charge AS to go up to +329:
A shadow steed rears back on its hind legs!
Shadow steeds sometimes have a spiritual warding attack (-20 TD pushdown) following successful melee hits:
A shadow steed stomps at you with its foot!
AS: +229 vs DS: +198 with AvD: +42 + d100 roll: +63 = +136
... and hits for 15 points of damage!
Blow raises a welt on your right arm.
CS: +194 - TD: +204 + CvA: +10 + d100: +56 - -5 == +61