Question: Who allegedly instituted The Eucharist?
About the article "Last Supper", section "Institution of the Eucharist".

Candidate passages:
"At the Last Supper, on the night he was betrayed, our Saviour instituted the Eucharistic sacrifice of his Body and Blood."
(Catechism of the Catholic Church 1323)Eucharist in the Catholic Church refers to both the celebration of the Mass, that is, the Eucharist liturgy, and the bread and wine which after the consecration are transubstantiated (changed in substance) into the body and blood of Jesus Christ, Lord and God, a declaration formulated by the Council of Trent with an anathema against anyone who denied this.
"Blessed Sacrament" is a devotional term used in the Roman Catholic Church to refer to the Eucharistic species (the Body and Blood of Christ). 
 Sunday.
The feast of Divine Mercy Sunday was instituted by Pope John Paul II and is celebrated the Sunday after Easter on the General Roman Calendar, and is associated with specific indulgences.
In an entry in her diary, Faustina stated that anyone who participates in the Mass and receives the sacraments of Confession and the Eucharist on this day is assured by Jesus of full remission of their sins and punishments. 
Celebration of the Christian mystery.
Seven sacraments.
There are seven sacraments of the church, of which the most important is the Eucharist.
According to the Catechism, these sacraments were instituted by Christ and entrusted to the church.
They are vehicles through which God's grace flows into the person who receives them with the proper disposition.
In order to obtain the proper disposition, individuals are encouraged to attend classes before being permitted by pastors to receive certain sacraments.
Participation in the sacraments, offered to them through the church, is how Catholics obtain forgiveness of sins and formally ask for the Holy Spirit.
These sacraments are: Baptism, Confirmation, Eucharist, Penance, Anointing of the Sick, Holy Orders, Holy Matrimony 
In Christian belief and practice, a "sacrament" is a rite, instituted by Christ, that mediates grace, constituting a sacred mystery.
The term is derived from the Latin word "sacramentum", which was used to translate the Greek word for "mystery".
Views concerning both what rites are sacramental, and what it means for an act to be a sacrament vary among Christian denominations and traditions.
The most conventional functional definition of a sacrament is that it is an outward sign, instituted by Christ, that conveys an inward, spiritual grace through Christ.
The two most widely accepted sacraments are Baptism and the Eucharist (or Holy Communion), however, the majority of Christians also recognize five additional sacraments: Confirmation (Chrismation in the Orthodox tradition), Holy Orders, Confession, Anointing of the Sick, and Matrimony.
Taken together, these are the Seven Sacraments as recognised by churches in the High church tradition—notably Roman Catholic, Eastern Orthodox, Oriental Orthodox, Independent Catholic, Old Catholic most Anglicans, and some Lutherans.
Most other denominations and traditions typically affirm only Baptism and Eucharist as sacraments, while some Protestant groups, such as the Quakers, reject sacramental theology.
Most Protestant Christian denominations who believe these rites do not communicate grace prefer to call them "ordinances".
Justin Martyr described the Eucharist: 
The Eucharist chalice from 1483 bears the name “Steph’ de Bernkastel”, who was the priest at that time.