The Passion of the Christ

The film opens in Gethsemane during the night as Jesus Christ (Caviezel), at the height of his cause, prays while his disciples Peter, James, and John (James' brother) sleep. After he wakes them and tells them to pray, Satan appears in a hooded androgynous, albino form, and tempts him with reasonable doubt, stating - "it is not right for one man to die for their (humanity) sins." Ignoring it and praying on, Jesus' sweat becomes like blood, and drips to the ground while a snake emerges from Satan's guise. Jesus hears his disciples call out for him, he rebukes Satan by stomping on the snake's head, and the latter vanishes.
After receiving a bribe of thirty pieces of silver, Judas, another of Jesus' disciples, approaches with a group of temple guards, and betrays Jesus (by confirmation of his identity) with a simple kiss on the cheek. As the armed guards move in to arrest Jesus, Peter takes a sword and cuts off the ear of Malchus, one of the guards and a servant of the high priest Caiaphas. Jesus, in turn, heals the ear. As the disciples flee, the guards secure Jesus, and beat him during the journey to the Sanhedrin.
John tells Mary (mother of Jesus) and Mary Magdalene of the arrest while Peter follows Jesus and his captors at a distance. Caiaphas holds trial over the objection of some of the other priests, who are expelled from the court. When questioned by Caiaphas whether he is the Son of God, Jesus replies "I am." Caiaphas is horrified, tears his robes in outrage, and Jesus is condemned to death for blasphemy. Peter, secretly watching, is confronted by the surrounding mob for being a follower of Jesus, and he denies this three times. A sobbing Peter flees, after remembering that Jesus had foretold this coping of a defense. Meanwhile, the guilt ridden Judas attempts to return the money he was paid to have Jesus freed, but is refused by the priests. Tormented by Demons, he flees the city, finds solitude, and hangs himself from a tree with a rope he finds on a dead donkey at dawn.
Caiaphas brings Jesus before Pontius Pilate to be condemned to death, but after questioning Jesus and finding no fault, Pilate instead relays him to the court of Herod Antipas as Jesus is from Antipas' ruling town of Nazareth, Galilee. After Jesus is again found not guilty and returned, Pilate offers the crowd option that he will chastise Jesus, and release him. He then attempts to have Jesus freed by the peoples' choice between Jesus and a violent criminal Barabbas. To his dismay, the crowd demands to have Barabbas freed, and Jesus killed. In an attempt to appease the moment, Pilate orders that he simply be punished. Jesus is brutally scourged, abused, and mocked by the Roman guards as "king of the Jews" with a crown of thorns. However, Caiaphas, with the crowds' verbal backing, continues to demand that Jesus be crucified as a heretic, and Barabbas released. Admonished, Pilate washes his hands (taking no responsibility) of the incident, and reluctantly orders Jesus' crucifixion. During the course of events, Satan watches Jesus' bloody sufferings with great interest.
As Jesus labors to carry a heavy wooden cross along the Via Dolorosa to Calvary, Veronica avoids the escort of soldiers, and wipes Jesus' face with her veil. Jesus is beaten, and pressed by the guards until the unwilling Simon of Cyrene is forced into carrying the cross with him. At the end of their travel, with his mother Mary, Mary Magdalene, and others witnessing, Jesus is crucified. The very act seems to affect the weathering condition of the earth itself. As he hangs from the cross, Jesus prays to God asking forgiveness for the people who did this to him, and redeems a criminal as a saint that is crucified next to him.
Succumbing to impending death, Jesus gives up his spirit, and dies. A single droplet of rain falls from the sky to the ground, triggering a sudden earthquake which destroys the Holy temple and rips the cloth covering the Holy of Holies in two, to the horror of Caiaphas and the other priests. Satan is shown screaming in agonizing defeat. Jesus' lifeless body is taken down from the cross, and entombed. In the end, the healed form of Jesus rises from the dead, and exits the tomb anew.

Question: What animal did Satan turn into?
Answer: A snake