The story revolves around a band of soldiers that conduct secret missions to prevent the Nazis from creating science fiction-esque weapons and armour that may sway the outcome of the war.
Before the you go on a missions you choose your 5-man squad from a pool of candidates plus a player-created character, equip them, and change their stats. The missions consist of turn-based tactical combat, switching to real time when no enemies are close by, similar to Jagged Alliance 2. Also like Jagged Alliance, players will interrupt the enemy if they have action points, sufficient level difference, and spot the enemy.
Unique to Silent Storm, the environment is fully destructable; you can shoot a small hole into a wall, allowing you to see the other side. If you keep shooting, you can make the hole big enough to crawl through and with enough bullets, will eventually destroy the entire wall. Taking out building corners cause even more destruction since the physics engine will determine that destroying a support-bearing corner will level an entire quarter of a multi-story building. Grenades and explosives can also destroy the environment and more powerful weapons will do more environment damage as well. This destruction opens up tactics as the player can choose to assault buildings and structures in the direction desired. So the game can be played as you want it to be played. You can sneak around taking each sentry out silently with a sniper or shoot out the floor from beneath the enemy or just blow everything to oblivion.
Line of sight and audible level are also important. Enemies that can't be seen but can be heard are shown as a red silhouette and can be tracked, fired upon and killed. Higher level, hidden characters are harder to spot.
Cosmetically, the game features rag-doll physics so that powerful guns and large explosions can send characters flying through the air.
There are various RPG elements:
- Each character's skills increase when used (e.g. marksmanship increases as he shoots more), as well as overall experience to level up
- 2 playable campaigns: Allies and Axis
- 6 professions: scout, sniper, soldier, grenadier, medic, and engineer
- Create the main character: personality, profession, properties and skills, customizable face
- 9 skills available per character
- Branching perks tree similar to Diablo for each class, allowing further customization of characters (e.g. increased critical hits, throws further, etc.) .
- Unused characters left in the character pool also gain experience and the computer automatically selects skills from the skill tree.
- Many realistic and sci-fi weapons, guns, grenades, and equipment with stats for firing speed, accuracy, damage, etc.