Hearts are through to the Scottish League Cup last 16 after capping their perfect group-stage campaign with a 3-2 victory at East Fife.
Livingston and Dundee also remain on full points as they each made it three wins from three.
St Johnstone's 100% record ended in a 0-0 draw with Scottish Premiership rivals Dundee United, who then edged the shootout 4-3 for a bonus point.
Ross County eased to victory, while Kilmarnock claimed their first points.
Championship leaders Hearts will be seeded in Sunday's draw, having ensured they will finish as one of the four best group winners. Two goals from Olly Lee in the opening three minutes and an Andy Irving effort secured victory, with Jack Hamilton and Ryan Wallace replying.
Raith Rovers are second in Group A, eight points behind Hearts, after Manny Duku completed his double in the 90th minute to rescue a 3-3 draw at home to Inverness Caledonian Thistle. Raith took the bonus point with a 3-2 penalties triumph.
St Johnstone relinquished top spot in Group C with an uneventful Tayside derby stalemate. Dundee United have played all their games and are a point clear of Peterhead and St Johnstone, who face each other on Saturday.
Peterhead dropped their first points in a 1-1 draw at Kelty Hearts before winning 5-3 on penalties.
Alan Forrest's early double sent Group H leaders Livingston on their way at bottom-tier Stenhousemuir, with Matej Poplatnik and Aaron Taylor Sinclair completing the 4-0 rout.
In Group B, strikes from Paul McGowan and Danny Mullen plus a Charlie Adam spot-kick helped Dundee see off nine-man visitors Cove Rangers 3-0. The League One leaders had Blair Yule and Jamie Masson were sent off before the hour mark.
Dundee are now above Hibernian on goal difference, with the two sides meeting in a group decider on Sunday.
At the foot of the group, Forfar Athletic triumphed 4-3 on spot-kicks after a 3-3 draw with Brora Rangers drew 3-3.
Callum Morrison hit a double as Falkirk won 4-0 at Dumbarton to finish on nine points in Group E. Danny Whitehill's double got already-eliminated Kilmarnock off the mark as they won 2-0 at Clyde.
Ross County moved top of Group D thanks to goals from Oli Shaw, Alex Iacovitti, Harry Paton and Charlie Lakin in a 4-1 Highland derby win at League Two Elgin City. Stirling Albion climbed off the bottom by beating Montrose 2-1.
Maxwell Wright and Kyle Fleming both netted twice as Annan Athletic moved top of Group F to finish on seven points following a 5-1 win over Albion Rovers.
Queen of the South also ended their campaign with seven points thanks to a 3-1 win over Queen's Park at Hampden in Group G.