The whole Silent Storm series is amazing (the original, the standalone expansion pack Sentinels, and Hammer & Sickle which I count as being part of the series since it literally has the same engine, assets, base gameplay, and even references the plots of the previous ones).

One really cool thing about them is they have very extensive enviromental destruction. It doesn't have a super-detailed physics simulation to it (so you won't see things actually collapse by falling over for example, if the engine runs a calculation and figures out that a particular bit of the level geometry doesn't have anything to stand on, it will just evaporate in a cloud of particle effects instead of falling to the ground), but it's still amazing, and it adds a lot to your tactical flexibility. One of your characters heard an enemy in the other room (which in the game is represented by having a silhouette showing an approximate position)? Well, you can just shoot through the wall. Locked door in your way? Why bother picking it when you can just have your machinegunner unlock it with a belt of 8mm Mauser.

They're also really cool to play if you're a gun nerd, they feature a lot of more obscure WW2-era weaponry, and probably the largest variety of grenade types and explosives I've ever seen (you can literally throw jars of pure nitroglycerin, which is rather ill-advised in real life).

Unfortunately all the physics stuff is really heavy and sometimes, in particularly extreme cases of destruction, the game will just have to sit there for a minute running calculations, and this isn't something that gets fixed by running it on modern hardware (since I'm guessing it only uses one core, although I haven't tested it, but it's from the age before it was clear that multi-core was the direction CPUs would go in, a lot of games from that time have no support for multi-threading).