The Gunners signed Pepe in a club-record £72m deal from Ligue 1 side Lille in the summer to complement Aubameyang and Lacazette in what looks like a potent attack on paper.
Arsenal manager Unai Emery resisted the temptation to start all three of his attackers until Sunday’s north London derby when the trio were named in his starting XI for the first time.
Lacazette and Aubameyang got on the score-sheet either side of the break, while Pepe provided a constant threat up against Tottenham’s makeshift full-back Davinson Sanchez.
The Arsenal club-record signing is still waiting to open his account for the Gunners, having netted 22 times and made 11 assists in Ligue 1 last season.
Former Liverpool FC captain Souness believes the Arsenal attack will prove devastating in the Premier League given the firepower at Emery’s disposal.
“I think they are three fabulous players and Pepe will be a star in our football,” Souness told Sky Sports.
“He did a couple of things in tight areas where he got the ball out of his feet and he’s a lovely striker of the ball.
“I think he’ll get a lot of goals in our football. Can you imagine those three away from home when teams are coming after them? They’ll score lots of goals between the three of them.”
Souness added: “Lacazette’s finish was sublime, Aubameyang’s finish was sublime and Pepe will get all sorts of goals. They will be a real handful for anyone. Whoever plays against them, you’ve got to be wary of them.”
Arsenal finished in fifth place in the Premier League table last term to miss out on a Champions League spot for the third consecutive season.
The Gunners lost 4-1 to bitter rivals Chelsea FC in the Europa League final.
Arsenal signed five new players as well as Pepe in the summer.
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