I've been waiting for this game to pop on GoG for years, now.
I'm nearing the end of the game (completed 27 missions out of 30) and it is quite close to Doom, but with a vehicle.
The game unveils in the US. Before each mission, we get to select one among one, two or three. Then, we are dropped in a map, with more or less enemies, many with different stats and gears.
In the map, we can collect lots of ammo, weapons, gears etc.
The goal, for each mission, is to capture the flag and bring it back to the start of the level. For that you'll have to trigger switches, destroy said amount of enemies, etc.
It looks a lot like Doom graphically, but is very original in its approach, where we drive a vehicle. Another original and sweet mechanic is the fact that we can exit and enter it whenever we want, and if the vehicle is destroyed, we get to play on foot.
This is where it hurts, on foot gameplay is really bad : the character is heavy, there's only one, unefficient weapon with unlimited ammo...Nothing near as good as the vehicle part.
And while this part is good, it also suffers from obese hitboxes. While it drives well, you'll often hit walls that you don't seem to even physically touch.
Apart from that, the game is quite easy. Although, near the end, one mission is bugged and forces the player to cheat to pass it.
Now, the game released in 1996 and I'd like to say it certainly took balls to have such a take on the FPS genre when it was rather new. It was original, it tried to bring something fresh to the gaming industry, it is not bad, so just for that 5/5, if you like this genre, it really smells like nostalgia.