I think you are a little confused about terms. The epiclesis is only one part of the Eucharistic Prayer. The epiclesis is the part of the Eucharistic Prayer during which the celebrant prays that God may send down His Holy Spirit to change this bread and wine into the Body and Blood of His Son. During the epiclesis the celebrant extends his hands over the bread and wine.
As the Catechism notes:
1353 In the epiclesis, the Church asks the Father to send his Holy Spirit (or the power of his blessing) on the bread and wine, so that by his power they may become the body and blood of Jesus Christ and so that those who take part in the Eucharist may be one body and one spirit (some liturgical traditions put the epiclesis after the anamnesis).
The transformation of the bread and wine into the body, blood, soul and divinity of Jesus begins at the epiclesis and concludes with the words of consecration over the hosts and chalice (Catechism #1333). It is not the elevation of the host and chalice that consecrates them, rather it is the words and intention of the Eucharistic Prayer.
Yes the priest only holds up a main large host after the consecration but all hosts and chalices on the corporal all considered consecrated. The corporal is a square white cloth upon which all ciborium and chalices that are intended to be consecrated are placed.
So, it is through the prayer that all the hosts and wine on the corporal become the body, blood, soul and divinity of Jesus.