Access is briefly mentioned in a Superman/Fantastic Four crossover. When Superman receives a (false) holographic message from his father Jor-El, stating that Galactus was the one who destroyed Krypton, he flies off, reflecting to himself "With the help of experts I'll find the monster. And to find them... I need Access."
Access is mentioned again in the crossover ''Superman/Silver Surfer.
Access' first appearance was foreshadowed in the 1995 DC/Marvel comic Green Lantern/Silver Surfer: Unholy Alliances, where the two heroes joined forces to stop Thanos and Parallax from destroying their universes. The final frames of the comic show an alleyway in New York where a large cardboard box is beginning to emit powerful beams of energy.
Access is now a native of both universes and his duty is to keep them separate. If they start to overlap, the universes will merge into the Amalgam Universe once again. Access must move from one universe to the other keeping people from crossing over. If he stays in one place too long, he can cause spontaneous crossovers to occur. Access usually works out situations like this without anyone noticing that he is involved (this is done to explain how the subsequent DC/Marvel crossovers occur. Stories where DC and Marvel heroes appear on a "shared Earth" are believed to be dimensional fluxes where the two universes have begun to merge again. It has also been explained that once Access has restored the timelines, the characters forget about the crossover).
Despite shared ownership between DC Comics and Marvel Comics, only DC has used the character in a non-crossover appearance. In Green Lantern #87, Access appears to the green-skinned Jade and claims to be looking for Kyle Rayner. Having no success, he decides to travel to the Marvel Comics universe in order to find the Silver Surfer.
Axel was just a normal teenager living in New York who came across an old bum in an alley, who protected what seemed to be a cardboard box but was actually a portal between the universes. He also revealed that Axel was next in line to bear the powers and responsibilities of being "The Access," the person in charge of preventing the universes from merging into one. This happens because they were originally one universe that split in two when The Brothers first fought; certain "fragments" of the original universe remained. The "box" was one of them—Access was another.
At the height of the Brothers' battle, when the last battle had ended- with the Marvel Universe being the overall winner with six victories to five-, the universes were combined into a single Amalgam Universe by The Spectre and the Living Tribunal to avert the end of existence. Access used shards of each universe hidden inside Batman and Captain America to separate and restore both universes. Aided by Batman and Captain America who, in many ways, were the Brothers in miniature, Access helped stop the fight between The Brothers, saving the two universes from destruction when the Brothers, looking at the two heroes, realised how foolish their conflict with each other truly was.