Dr. Helsing is able to defeat monsters by placing a torch which casts light across the playing field. This light is blocked and obstructed by walls and buildings that are in the way and thus strategic placement of the torch is necessary. To actually destroy the monsters, Dr. Helsing utilizes various color-coded tonics which release shockwaves that damage creatures of the same color. All of the monsters are color sensitive, and can only be damaged by a tonic of identical color. More advanced monsters hvae shields of various colors which absorb a single point of damage from a tonic and thus multiple tonics must be used to defeat stronger monsters.
The game's main mode is a standard campaign that follows Dr. Helsing and Raffton through villages which are occupied by the shadow blight. Helsing's Fire also features a survival mode which provides a set amount of time to complete a wave of enemies while each wave gets progressively harder. It also has a bounty mode which is ranked leaderboard play in which you try to complete specific puzzles with the least amount of tonics used.
- Rats - The most basic monster that has no special attributes
- Skeletons - These monsters will attack Dr. Helsing's torch if it is placed too close
- Fair Maidens - Humans that are need to be rescued
- Ghosts - These are only visible in the dark
- Werewolfs - These turn into humans when damaged by tonics
- Lagoon Archers - These will shoot an arrow at Dr. Helsing when damaged by a tonic
- Automatons - These robots have shields that block tonics and light
- Giant Bats - These fly to a different location when attacked
- Acolytes - These have better mobility and feature multiple attacks