The Norwegian shone with a 143m jump in the first discipline before compounding his advantage in a flawless cross-country race to win by 46.4 seconds.
A superb opening jump had already put Riiber in the ascendancy, with the 152.6 points he accrued seeing him start the second leg of the day 30 seconds clear of the field.
From there, there was only going to be one winner – with Riiber beating teammate Joergen Graabak to take top spot on the podium.
Graabak in turn fought off the attacks of Germans Fabian Riessle and Vinzenz Geiger to claim the silver medal in a dramatic sprint finish.
Riessle bagged the bronze – having sat 11th after the ski jump – just 0.1 seconds ahead of his teammate Geiger in a photo finish.
The victory means Riiber has taken all four victories in the Nordic Combined World Cup this winter, following up his triple-header of Ruka successes last time out.
He leads the World Cup standings by 145 points from Graabak, who made it back-to-back second places while Jens Luraas Oftebro wraps up the top three a further 30 points back.
Oftebro, among the four Norwegians who occupy the top four spots, had reached the podium in his previous three outings but had to settle for fifth this time around.