Morrowind:Summon

Summons a creature to fight for the caster for a limited period of time. Summoned creatures will disappear when the spell expires, when they are killed, or when the character who cast the spell is killed.

Notes
You can harvest souls from summoned creatures if you cast Soultrap on them before they are killed.  (You will not receive a soul if the summon spell expires, only if the summoned creature is killed.)  Golden Saints are the best for this, as they have the largest souls available short of a few unique deities.
Those born under the Atronach birthsign can use summons such as the Ancestral Ghost to replenish their magicka, by summoning a creature, striking it three times, and then absorbing the spells it casts.
There is a short period of time after a summoned creature is killed during which you can loot its corpse just before it vanishes.  While most summons do not carry anything of much value, a few can be exploited in this way to harvest their gear.  Most notable for this are the Dremora, which carry a random high-quality weapon (Dwarven, Ebony or even Daedric), and the Golden Saint, which is armed with a good weapon and shield.  (This is one of the only ways to acquire a Daedric Tower Shield.)  See charts at the bottom for a description of the loot obtainable in this way. When exploiting this glitch, it is suggested to save, since the game will sometimes freeze when you try to take the item off the summoned creature. Looting the corpse of a summon and choosing "dispose of corpse" will always freeze the game, as this conflicts with the script that is supposed to remove the corpse.
Combining a 1 second summon and a 1 second Soultrap on target into one spell and firing it at the ground beneath you will result in a permanent summon.
Multiple creatures can be summoned at once, as long as they are different creatures or are in separate spells.
Creatures summoned using a constant enchantment do not automatically reappear. They instead die. As with the invisibility CE, the player has to re-equip the enchanted item.
Many summoned creatures are immune to normal weapons. This makes them useful defensively against most creatures and many NPCs.

Summons

  These five summons are different from all other summons in a few ways.  First of all, nobody sells the spells.  The only way to acquire them is by performing various quests.  (For the spell Dwemer Animunculi which summons a Centurion Sphere, read the book Secrets of Dwemer Animunculi. Summon Fabricant is an enchantment only available on Barilzar's Mazed Band from the Tribunal Main Quest.  For Call Bear and Call Wolf, you will need to complete several quests for the Bloodmoon Main Quest as a human (The Totem of Claw and Fang for Call Wolf and The Ristaag for Call Bear).  For Summon Bonewolf, you'll need to do the Bloodmoon Main Quest as a werewolf.)  Secondly, unlike the other summons, you may not create your own custom versions of these spells (for longer duration, etc.) or enchant the spells onto items.  The only versions of these spells that can exist are the ones you're given by the aforementioned quest events.

  Note: The creature IDs "golden saint_summon" and "winged twilight_summon" contain both a space and an underscore. The space keeps the summoning's name consistent, and the underscore keeps the ID code consistent.

Loot Types

|
Golden Saint Weapon

|

Golden Saint Shield

|}