Paul and Peter
Paul is portrayed with a sword, the tool of his martyrdom, Peter with a bowl, his characteristic attribute. They are understood to be Jesus’ appointed founders of the Church.
On the right side of the second register we happen upon Judas again. It’s the moment when the Apostle meets with the high priests, accepts his payment and shows them to the place where he will betray Jesus with a kiss.
Although Judas is normally shown already holding the money at the Last Supper, it is by no means clear when the transaction takes place - the Bible does not give us any definite indication.