Talk:Gilgamesh/@comment-31867253-20190121133637/@comment-28209103-20190418040446

AFAIK the requirement of to be still alive is merely a speculation  The requirement of Grand Caster is simply said to possess some sort of powerful claivoryance skill

The reason Merlin are summoned as mere caster is simply because we can't prepare a Grand Vessel. A Grand Vessel is unique to the Alaya and can only deployed when will of humanity are aware of the existence of beast.. but by that time the world as we know it should be gone because the threat known as beast.

This is because will of alaya is not omnipresent and omniscience, even magus are capable of avoiding their observation.

Servant system is a system where heroic spirit are summoned inside a vessel prepared before hand and said vessel will modify the trait of said heroic spirit.

e.g Cu as Caster lose a lot of his agility that he gained as lancer. Euryale and Stheno are weaker than average men in live but gained stronger body as Servant. Angry Manjew is just normal boy without any combat ability but at least stronger than average adult as servant.

Hence grand vessel can be thought as some sort of special vessel (Servant system is poor imitation of this system might I add) that cannot be used by even magician like Justeaze which is the one who created Fuyuki servant vessel system... or maybe given their goal of reaching alaya such OP vessel is uneeded.

To put it simply the reason Merlin and KH is summoned as normal Caster and Assassin is that we're summoning them in normal vessel post their death. Were their help is needed it is certainly possible that they'll be called for emergency avenger assembly as Grand servant