The big leak contains unreleased and pre-release content from Bungie-era Halo games from Halo CE up to Halo 3 and Reach.

On Friday, a new gaming industry leak hit the internet, and this time it involves 25 years of Halo franchise history including a demo from 1999.

A massive Halo leak has revealed more than two decades' worth of unreleased data pertaining to the franchise, including cut content and more.

After Insomniac Games, Rockstar, and the Pokemon Company were all hit by major leaks in recent years, Halo Studios has now fallen victim to a similar situation where almost 25 years of vaulted content from the shooter series has spilled onto the internet.

Over 25 years of Halo content has leaked online, including playable builds from before the iconic first-person shooters series joined Xbox – or was even an FPS.

The team claims that Microsoft neither paid them for their efforts nor provided resources and it appears that someone else decided enough was enough so a massive amount of content is now out in the wild for the PC community to do with as it wishes.