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"These mountains be in the heart of the land. At the base of this crag, thou wilt find a hamlet. They who have passed the Spell of Evocation from generation to generation, down through the ages, dwelleth therein."
P'ung Ryong on evocation in Chek

The Spell of Evocation is the secret summoning technique used to call Endless into the world of Breath of Fire IV. It is practiced by mediums in the village of Chek. It is a well guarded secret, kept from the world.

The Fou Empire also seeks the secret of the Spell of Evocation. They tried to create their own version of the spell, which led to the imperfect split summoning of Fou-Lu and Ryu. The ritual was executed at Mukto, a cliff near Kwanso on the Western Continent.

Rasso was looking for this secret when he mercilessly killed women and children in the Abandoned Village. He seems to be able to summon his own minions Joh, Ymechaf and Ight. General Yohm also seems capable of summoning minions as seen by Kham and Khafu.

Despite similarities and references, it is not explicitly stated whether and how these techniques are linked.