The Red Talisman can be found in the north of MAP35: Factory: Production (Strife) at the back of the temple. This item will become unlocked when all major enemies are defeated (Crusader).
This quest item was added in the 2014 The Original Strife: Veteran Edition. Collecting all 3 (Blue Talisman, Green Talisman, Red Talisman) grants a permanent super strength power-up and the Berserk Reborn Achievement.
Note: This item cannot be found if player is following the Bad Ending path.