Avengers: Shards of Infinity (2018 series) #1

Black Widow infiltrates a terrorist group called L.U.N.A.R. (Life Under Natural Authoritarian Rule) and makes off with a box. She then meets with Captain America, Black Panther (T'Challa), and the Falcon, telling them about L.U.N.A.R., a group bent on world domination led by a fanatical woman named Irma Krakov. They have a Vibranium-powered superweapon, but that's not the worst part: the box Natasha stole from them contains a fragment of the Cosmic Cube. And they already have a Cube fragment so they will likely move up their timetable....

From their base on the Moon, Madame Krakov orders a test for their Cosmic Cannon by shooting down a Helicarrier on Earth. But the Avengers arrive, infiltrating the base and fighting their way through autonomous weapons and living guards to reach the main chamber. As the Cannon recharges, Black Widow goes toe-to-toe with Krakov, beating her up while they debate philosophy; Cap defeats super-henchman Klove, likewise while talking about ideals and weaknesses and the like. The Cosmic Cannon gets ready to fire so Black Panther puts his Vibranium gauntlets onto the Cosmic Cube shard, causing a dangerous overload. The Avengers quickly return to the Quinjet while the L.U.N.A.R. moon base blows up, as most of the baddies also escape in time.