Universal Soldier was a series written by Alan McKenzie. It first appeared in 2000 AD progs 537-540 and 542-543 with art by Will Simpson. Subsequent series were published in progs 672-682 (art by Simon Coleby) and progs 750-759 (art by Brett Ewins and Zac Sandler). Max Brewster, the eponymous Universal Soldier, is a fighting genius who can adopt the personality of a famous warrior from anywhere in the timeline to make him the world's deadliest combatant. Unfortunately, he can only do this because of a 'storyge chip' implanted in his brain by the dastardly Universal Corp PLC, who used him as a human guinea pig after he was severely brain-damaged while working for them. It is rumoured that Max and Friday occasionally meet up for a pint to talk about "how capitalism ruined our lives," "the evils of big business" and "ten ways to disembowel a man with common household objects."
Universal Soldier also spawned a spin-off series starring classic Valiant character Tim Kelly, which proved to be something of an embarrassment after 2000 AD's publishers discovered they didn't actually own him.