The world number one arrived in the Irish capital fresh from wins in Brighton and Nottingham, and he maintained his dominance with Night Eight success in the Emerald Isle.
Humphries recorded a trio of ton-topping averages to scoop the £10,000 bonus prize, defeating Peter Wright, Nathan Aspinall and Michael Smith to extend his lead at the top of the table to seven points.
The 29-year-old opened Thursday's proceedings with a comprehensive 6-1 success against Peter Wright, averaging 106 and producing two stunning ton-plus checkouts in the process.
This set the tone for another memorable night for the World Champion, who crashed in six 180s to overcome a spirited Nathan Aspinall in the semi-finals, in a repeat of last week's Nottingham final.
Humphries then produced another merciless display to topple Smith in the evening's showpiece, kicking off the contest with legs of 12, 13 and 11 darts to threaten a record-breaking average.
Smith converted 113 and 125 combinations to win his two legs, although it wasn't enough to deny Humphries a ninth consecutive victory in the Premier League.
"The last three weeks have been fantastic," Humphries told Sky Sports afterwards.
"The standard has been high. I'm not unbeatable but I'm putting in that stage of performance where it takes something big to beat me and nobody has done that so far.
"I'm just happy with the way I'm playing and if I keep playing like this then it will take a tough performance to beat me – that's all I ask of myself.
"If someone beats me and I play well then I'm not too disappointed but the last three weeks have been a dream.
"I'm really pleased with the fashion I've won the last three nights."
He later added: "At the start of the season it felt really tough for me, but now I'm enjoying the game, and that's when I'm at my best.
"I feel much more comfortable now. I feel like I belong here, and the last three weeks have just been fantastic.
"I know I'm not unbeatable, but I feel like I'm playing at a level where it's going to take a big performance to beat me.
"I loved tonight. It was the loudest crowd I've ever played in front of. The atmosphere was incredible.
"As I said last week, I have got Irish heritage in my family, and I'm sure my Mum will be super-proud tonight, so it's a really special feeling."
