Fear Effect features gameplay with unshaded characters textured to resemble cel-shading, notably being one of the very first games to utilize the technique. Rather than using pre-rendered 2D backgrounds, the environments are composed of streaming or looping full-motion video. As a consequence, the game is composed of four discs. There are also puzzles interspersed between action sequences, similar to other games of the survival horror genre. The player controls one of three mercenaries (either Hana, Deke, or Glas) through areas filled with human and non-human enemies. The game controls are similar to traditional survival horror tank controls, with an exception being that the characters can run and shoot simultaneously. When wielding two guns (one in each hand), they are also able to shoot multiple enemies at the same time. Another feature is the ability to duck and roll; while facing a number of the armed foes, the player can roll a short distance and avoid taking enemy fire. The game's title refers to the player's life bar, a meter which resembles a pulsing EKG. When the player is damaged, the green line of the EKG will pulse faster and turn red. It is possible to 'regain' health by performing acts that will calm that character's heart rate. These include solving a puzzle or sneaking behind a guard to perform a stealth kill. Both will be rewarded with a health boost that brings the meter back to green.