Tyr is the god of war, law, and justice. He is routinely depicted with a missing right arm, and holding a spear or a scepter.
Tyr was a god of war and a son of Odin, but he was primarily associated with law, justice, and the swearing of oaths. His most well-known tale concerns the binding of the wolf Fenrir, one of Loki’s sons. As Fenrir grew older, he became more fierce and large, which began to worry the gods and goddesses. They kept him as a guard for Asgard, but they soon realized they would have to bind him up. They went to the dwarves who forged a chain that could not be broken, but Fenrir knew something was wrong. He agreed to allow the gods to put the chain around him if one of them would put his arm in his jaws for insurance purposes. Only Tyr was brave enough to approach the wolf and place his arm in his mouth, knowing that he would lose his arm once Fenrir discovered he could not escape from the chain. Fenrir bit Tyr’s arm off, leaving Tyr with only his left hand, but the knowledge that he made the sacrifice for the safety of Asgard was enough.
At one point, Loki insulted Tyr saying that he could only incite conflict and never resolve it. This points to Tyr being a war god in addition to being concerned with law and justice. However, Tyr was also viewed as the ever-prudent jurist who weighed things fairly and granted justice appropriately.
Tyr is prophesied to kill and be killed by Garm, the guard dog of Hel during Rangarök. It is also during Rangarök that Fenrir finally gets free, swallowing Odin whole and fulfilling the prophecy of his death.