Bound by Flame is an action RPG set in a fantasy universe. The player controls the mercenary Vulcan who protects the lands against a siege by the seven ice lords and their minions. He starts as an experienced fighter in the game, but early on he messes up summoning a fire demon and instead becomes possessed by it. This introduces a duality that forms the backbone of the game, as he can either attempt to restore his humanity or give in to the possession and embrace the powers. This change is guided through his actions, either helping villagers or working against them, and not only leads to visual change - either restoring the human form or slowly transforming into a fiery demon - but also to branching story paths with multiple endings.
The game offers three skills trees: fighter, ranger, and pyromancer. Each tree has its own abilities, such as melee combat, stealth, and fire magic. The player can choose from four tiers for each skill, narrowing down the choices with each new tier. All of the paths lead to an ultimate ability. While fighting, it is possible to switch stances between warrior and rogue. The game also includes companions, weapon crafting, and a variety of modifiers.
The game world is divided into smaller hubs, one for each chapter, offering freedom to explore and complete quests in any order until the entire hub is finished. A mini-map is available in the bottom right corner to help navigate areas.