Patrick Mahomes passed for 378 yards and rushed for 69 as the Kansas City Chiefs advanced to their fourth straight AFC championship game, outgunning the Buffalo Bills 42-36 in overtime in a divisional round thriller at Arrowhead Stadium.

Mahomes completed an eight-yard touchdown pass to Travis Kelce on the first possession of overtime, which prevented the Bills from ever getting a chance in the extra session in an epic showdown for what could be a special rivalry for years to come.

"With that coaching staff and the players they have, there's going to be a lot of battles" said Mahomes. "I'm glad we got this one. We're going to try to keep it rolling. We've got a good team coming in next week."

Kansas City, the number two seed, claimed their 11th win in 12 games but will host the AFC Championship game next Sunday against the one opponent that beat the Chiefs during that stretch, the Cincinnati Bengals.

All of the Chiefs' AFC Championship appearances since Mahomes became their starteR have been at home, with the last two resulting in Super Bowl berths.

The teams each scored twice inside the final two minutes of regulation, racking up 25 points during that dramatic window. Kansas City forced overtime on a 49-yard field goal by Harrison Butker as time expired.

Before that, Bills quarterback Josh Allen fired touchdown strikes of 27 and 19 yards to Gabriel Davis, the last coming with 13 seconds remaining.

Mahomes responded by hitting Tyreek Hill with a 64-yard touchdown. Later, when he took over with 13 seconds left, he hit Hill for 19 yards and Kelce for 25 to improbably set up Butker.

"Every time he (Mahomes) comes in the huddle, he says, 'Let's be great', and it's not corny when he says it," Chiefs coach Andy Reid said.

Bills coach Sean McDermott termed the performance a "tremendous effort by Josh", who connected with Davis for four touchdowns, while finishing with 329 passing yards and 68 rushing yards. Davis caught eight passes for 201 yards.

Buffalo saw their five-game winning streak end, suffering a postseason loss for the second straight year in Kansas City.

"Josh played his ass off," Mahomes said. "This was a great game between two great football teams and at the end of the day, Tyreek and Travis made plays to win the game."

Mahomes finished 33 of 44, with three touchdowns and 11 strikes to Hill for 150 yards.

Kelce added 96 yards on eight catches.

Allen engineered a 75-yard march in 75 seconds, firing an 18-yard touchdown pass to Davis with 37 seconds remaining to forge a 14-14 halftime tie. Buffalo also scored on their first drive, converting two fourth downs, including a one-yard touchdown rush by Devin Singletary.

Mahomes manufactured touchdown drives of 11 and 12 plays in the first half. He rushed for 49 yards on the first series, including an eight-yard score, and found Byron Pringle for a two-yard touchdown pass.

For the half, Mahomes totalled 163 yards and Allen 158.