The Kaidon (or "Clan Leader")  is a Sangheili dynastic rank. The head of a Sangheili State is referred to as "Kaidon." Kaidons are chosen by the previous rulers of the specific state. The Sangheili "Clan Leader" seems to be more of a political position than a military position.
After crowning, it is considered common that any Elder who disagrees with the crowning of the new Kaidon send one or more assassins to kill him or challenge the Kaidon himself, as a form of testing whether the Kaidon is worthy of ruling. Should the assassins fail, the sender is most likely executed, an example being Koida 'Vadam, the Elder that attempted to have Thel 'Vadamee murdered. However, if the Kaidon is killed, no action is taken against the Elder, as the Sangheili believe that a Kaidon who cannot defend himself is unworthy of leadership. The Kaidon, despite being a political ruler, is still very active in the military, even leading long time campaigns into enemy territory, leaving the Elders to rule in his stead. Kaidon is a lifelong rank, so the next Kaidon is only crowned after the current Kaidon dies.
- Ripa 'Moramee had a desire for greatness, so he attempted a coup on his own Sangheili Clan Leader on Decided Heart; however, it was a failure. He was punished for this attempt by being promoted to Arbiter.