Those search terms linked to a series of posts I did in 2010 about Judas, the most popular of which shared some reflections on how Judas and his suicide have been portrayed in art:
Historically, there are a couple of recurring motifs in depictions of Judas.
First, Judas is often wearing a yellow robe. Yellow represents greed (the color of gold) and cowardice. Judas is also often depicted clutching a money bag. Again, this symbolizes his greed. Finally, Judas is often depicted as having red hair. This is a symbol of the satanic. Below are some examples of these motifs in portrayals of the betrayal in the garden (click on the pictures for a closer look):
Giotto's The Kiss of Judas (1304-06) shows the red hair and yellow robe (on the left you also see Peter cutting off the ear of the servant):
This Kiss of Judas from the 12th Century shows the yellow underneath Judas' robe (showing us his hidden but "true colors"). Judas is also clutching a money bag. Peter is again depicted cutting off the servant's ear on the bottom left. Like the depiction above, note how Peter and Jesus have halos. Judas does not:
These motifs can also be seen in depictions of the Last Supper. All four motifs--yellow robe, money bag, red hair, missing halo--are seen Joan de Joanes' The Last Supper (1565). Judas is on the far right, leaning away from Jesus:
As many Judas scholars have noted, the gospels of Luke and John add diabolical details to the Judas narrative, portraying Judas as in league with the devil. Thus, devilish motifs also show up in portrayals of Judas. Consider the demon who hovers behind Judas (still in yellow and with red hair) in Giotto's The Pact of Judas (1303-05) as Judas arranges with the Jewish leaders to betray Jesus:
Some other satanic motifs are seen Cosimo Rosselli's The Last Supper (1481). Note how Judas is completely separated from Jesus and the Twelve, isolated on the other side of the table. Compare also the color of Judas' halo with the halos of Jesus and the Twelve. Also, Judas has a cat behind him. Cats, as satanic familiars, were often added to depictions of Judas:
Finally, demonic details have also been added to depictions of Judas's suicide. For example, in depictions of Judas's suicide we often see the soul of Judas (depicted as as a small person leaving the body of Judas) taken away by a demon. Consider this glasswork from 1520:
As seen above, from the early years of the church to the Renaissance the depictions of Judas were almost universally harsh, highlighting his cowardice, greed, or diabolical nature. However, since the Renaissance portrayals of Judas have become increasingly ambivalent. Judas shifts from being evil to tragic, evoking sympathy and empathy. My favorite example of this take on Judas comes from Nikolai Ge's Conscience, Judas (1891):
In Ge's painting we see, in the upper right corner, Jesus being taken away in the fading torchlight of the soldiers. Judas stands alone, clutching himself (not a moneybag). He is without Christ in the darkness. Ge's Judas looks like a figure of profound desolation and isolation. And as you see Judas standing there--alone in the dark--your heart breaks for him.