Randyll Tarly

Lord Randyll Tarly is a recurring character in the fifth and sixth seasons. He debuts in "The House of Black and White" though he had been mentioned in every season before that.

Season 5
Kevan Lannister, before leaving, suggests to Cersei Lannister that Randyll Tarly would be a good candidate for Hand of the King. Cersei refuses to put any more Tyrells or their supporters on the Council.

Randyll Tarly makes his first appearance in "The House of Black and White" as an advisor to Mace and Olenna Tyrell in the Small Council. He is ordered by Cersei to head to the Riverlands and "establish security" and rebuilt the wartorn area. Randyll sets out with his army, with Cersei actually ordering him to leave in order to remove Tyrell influence from King's Landing.

Brienne of Tarth and Podrick Payne cross paths with him while searching for the Stark girls. Randyll is dispensing harsh but fair justice in the marketplace of Maidenpool, which he is rebuilding. Randyll forces her to explain her mission, but allows her to go. He points Brienne in the direction of a group of brigands located in Cracklaw Point which may have the Stark girls. Brienne would return to Maidenpool with the heads of the brigands but not the Stark girls.

When Margery and Cersei are imprisoned by the High Sparrow, Qyburn informs Cersei that Randyll and his army are en route back to King's Landing to rescue Margaery.

Season 6
When Mace Tyrell returns to King's Landing, Randyll and Kevan Lannister greet the lord. The two explain that due to a lack of evidence, Margaery was released from imprisonment and is now in Randyll's care. Randyll then explains she will have to undergo an official trial later, unfortunately. Kevan, as the new Regent, appoints Randyll as Master of Laws.

Following the capture of Storm's End by Aegon VI Targaryen and the Golden Company, Kevan sends Randyll and his armies south to defeat them. At a parley with Aegon and Jon Connington, Randyll, instead of fighting, bends the knee and swears fealty.