JP Duminy's 41-ball 85 helped Winnipeg Hawks edge past Toronto Nationals by two runs on D/L method.
Brampton Wolves suffered a stunning collapse which saw them being bundled out for 103 from a comfortable position at 65-1.
Heinrich Klaasen's unbeaten contribution of 64 off 34 balls pipped Montreal Tigers to qualify for the playoffs.
McCullum finishes his career as T20 cricket's second-highest run-scorer, behind Chris Gayle in the distinguished list.
Chris Green snapped up two wickets and later contributed 30 runs in his side's comfortable chase of 137.
Daniel Sams' exquisite spell of 4-25 was backed by steady knocks from Shoaib Malik and Chadwick Walton to award Vancouver with yet another win.
Mohammad Hafeez and Anshy Rath were the heroes of the Royals' towering chase as the duo struck quickfire fifties to flatten the Hawks.
George Munsey's fluent 36-ball 66 came out on top against Yuvraj Singh's rapid half-century as the Nationals lost by 11 runs.
Wahab Riaz, Faheem Ashraf included in 20-man shortlist for England Tests
Shan Masood's a bit annoying to bowl at, says Jofra Archer
'We maintained a reasonable run rate considering the conditions' - Shan Masood
The flair, the calmness and the promises: Pakistan's rhetoric in the lead up to first Test
Broad takes 500 Test wickets, Woakes bags five as England reclaim Wisden Trophy
'Plans underway to stage remaining PSL matches this year' - PCB
Babar Azam fluency tames sloppy England on rain-curtailed opening day
Pakistan grapple with selection predicament as fired up England eye strong start
England roar back into the contest after 14 wickets tumble on day three
Team Green put on improved batting display after Naseem Shah shines again