The 29-year-old opened the scoring after five minutes, poking home from Aaron Ramsey's cutback, before sealing the Gunners' place in the Europa League quarter-finals with a tap-in from Sead Kolasinac's low cross.
The Gunners striker had been struggling for goalscoring form going into this game and the relief on his face was evident.
As he celebrated his goal with the Arsenal fans, he jumped into the crowd to grab a mysterious bag and when he came back onto the pitch, he pulled out a mask.
The former Borussia Dortmund striker then pulled a mask from the Marvel film Black Panther over his face before picking up a yellow card for the celebration.
Asked about the motive behind it, Aubameyang told BT Sport: "I needed something, a mask to represent me and the Black Panther represents me.
"In Gabon, we call the national team the Panthers so that's why I wore it."
It's not the first time Aubameyang has celebrated in such a manner. When playing for Saint-Etienne in France, he wore a Spider-Man mask and at his previous club Dortmund, he produced a Batman disguise after scoring in the Bundesliga.
The Arsenal striker missed his chance to grab a hat-trick late on against Rennes after squandering two big chances and revealed afterwards that there were some nerves at the end.
"[We were] a bit nervous. We took a while to close the game and I missed two chances but it was important to win tonight," he added.
"The most important thing is that we won and everybody is happy and proud."