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.
Naseem Shah earns maiden central contract; Mohammad Amir, Wahab Riaz left out
Babar Azam confirmed as Pakistan's new ODI skipper
Afridi buys Mushfiqur's bat to raise funds for virus affectees in Bangladesh
3 players who may have played their last PSL
PCB plan to hold pre-England tour camp from early June under ‘strict bio-secure environment’
England tour could get green signal as PCB and ECB hold positive talks: reports
Pakistan's tour to Ireland for two T20Is postponed
Faheem Ashraf, Kieron Pollard's Northamptonshire contracts cancelled
'Keeping fingers crossed' - Babar Azam hoping for T20 World Cup to get underway
ICC publishes guidelines for safe resumption of cricket