A fifty from Shimron Hetmyer and contributions by a number of his West Indies teammates has extended the hosts' series lead over Australia in Saint Lucia.
Hetmyer's second T20I half-century was complimented by a knock of 47 from Dwayne Bravo, as the pair combined in a fourth-wicket partnership of 103.
Andre Russell's 24 from just eight deliveries lifted the hosts to a total of 196/4, a total well out of reach for the travelling side, who struggled to build partnerships in response, eventually falling for 140.
Just like the first T20I, Aaron Finch won the toss and elected to bowl on the same surface, with left-arm orthodox bowler Ashton Agar's arm ball cleaning up Andre Fletcher in his first over. Josh Hazlewood carried his fine form from the first match, removing Lendl Simmons (30) with a smart piece of bowling.
Mitchell Marsh picked up the scalp of Chris Gayle when he chopped on for 13 in the eighth over, though Australia's buoyant mood was short-lived as Bravo and Hetmyer went about their work.
The pair moved things along at better than ten an over during a tricky middle-over period, hitting seven sixes between them.
Only a run out could end the partnership, as an effort from Matthew Wade and Josh Hazlewood caught Hetmyer out of his ground for 61.
The wicket provided no respite for the tourists, as Andre Russell entered for the last two overs. Striking two fours and two sixes in his eight-ball assault, he and Bravo struck 32 runs in the final two overs.
Wade (0) fell in the first over of Australia's reply, with Sheldon Cottrell's short-of-the-length delivery mistimed to Russell at mid-on, while Aaron Finch (6) couldn't make the most of a dropped catch by Andre Fletcher, as he was undone by a quality slower ball from Fidel Edwards.
Edwards left the field shortly after clutching his shoulder, the only sour note of the West Indies performance. Edwards' teammates kept the foot to the accelerator, as leg-spinner Hayden Walsh Jr tore the Aussies apart with figures of 3/29 from his four overs.
Walsh claimed Josh Philippe (13) and Moises Henriques (19), and eventually the scalp of Mitchell Marsh (54), with his second consecutive T20I fifty the only score of note for Australia.
A mix up between Ashton Agar (1) and Daniel Christian (9) broke up the last recognised Australian batting partnership, as Bravo, Cottrell and a wicket for Chris Gayle bundled the tourists 56 runs short.
After playing matches on back-to-back nights, the teams face off again in Saint Lucia on Monday night.
Personalise your homepage with an ICC account
News, fixtures and updates tailored to your favourite team. Never miss a moment!