Starting with Surefire Comics 1, June 1940, Ace Magazines was a company that was active until 1956 and portrayed the adventures of many super heroes.

In the Fox Multiverse their earth is known as Earth-A and has the distinction to be the first known superhero earth to discover the existence of other realities.

Scattered adventurers existed throughout time, such as the old west's Crossdraw Kid and the Ancient mystic known later as "The Old Man of the Pyramids".

In the 1930's Earth-A saw the advent of numerous adventurers, including the pulp mystery man known as The Raven. The Moon Man could be said to be this alternate reality's first masked/bubble headed man. Others were active such as Secret Agent X and the Black Spider

More traditional superheroes in flashy costumes and possessing startling powers and abilities began to appear in the public eye in the early months of 1940. The very earliest was the fastest man alive, Lash Lightning, who debuted in January 1940.

By the end of 1940, Lash had met up with many other heroes of his earth and at one team up in early 1941 it was suggested that a team be formed. Founding members include:

Lash Lightning

The Raven

Black Spider

Magno and his young sidekick, Davey

Marvo the Magician

The Sword

Vulcan

Others would join later including Lightning Girl, Captain Courageous, The Flag, Unknown Soldier and others.

One day late in 1940 or at the start of 1941, Lash Lightning accidentally discovered that at top speed he could cross from one vibrational pattern to that of another plain - to parallel worlds!

In July 1941 the Aces as a team arrived on Earth-B, but this event had been foreseen by Professor Q of Earth-B by looking 3 months ahead (the limit) in his "time viewer".

The Cyclones (Earth-B's team) was waiting and even though only half the Aces had come (the other half had travelled to Earth-C - their mission was to look for the cure to a common ailment on most earths, but fatal on theirs) a deadly battle ensued with casualties on both sides.

The newly joined Flag and Vulcan were killed in combat and The Raven expired under questioning after his capture. Volton of the Cyclones was killed by Magno the Magnetic Man.

Having viewed this probable future back in April, Professor Q made the decision to avoid the encounter - the Aces went about their mission unmolested in July and the above events did not manifest. Afterwards the Aces returned peacefully to their own earth.

Earth-B's speedster, The Tornado was secretly sent to Earth-A to spy on the Aces (Professor Q had observed their transit point and reverse engineered a way to use the speed of Tornado and Volton to open the breach between earths) and that enabled them to find out about Earth's A, C and D and also the existence of a group of multiverse defenders called the Hypernauts.

Not long afterwards, the attack on Pearl Harbor led to the Aces concentrating on fighting against the Axis and costumed threats on their own earth - it is known that the heroes of Earth-A did not engage in extra-dimensional travel for at least a decade after this point.

The history of Earth-A was obscured after the second world war, but their course of events seem to veer close to multiversal constants - a Korean War, Vietnam etc.

One event is known. In 1963 the speedster hero of Earth-F, The Lynx, encountered Lash Lightning under unrevealed circumstances.