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.
Hasan Ali returns to Test side, Pakistan name nine uncapped players for South Africa series
Ben Dunk leaves Melbourne Stars midway through Big Bash League
PSL 2021: How the squads stack up after the draft
Injury-afflicted Rumman Raees roped in as bowling consultant for Islamabad United
Heinrich Klaasen named captain of second-string South Africa squad for Pakistan T20Is
Umar Gul appointed Quetta Gladiators bowling coach
'Our security guys have said it is safe' - Boucher excited about historic Pakistan tour
IPL 2021: KXIP release Maxwell, Mujeeb; Finch, Moeen not retained by RCB
'Hope the objective of Cricket Committee meeting is not to grill someone' - Misbah-ul-Haq
Mohammad Amir to play for London Spirit in inaugural edition of The Hundred