Death is a great teacher. Failure in Intruder is the greatest way to learn where you should have gone, what you shouldn't have done, and how you could have done better. Intruder players spend a lot of time learning -- consequently, they are always getting better.
Growth is an important factor in Intruder, especially if you're coming into Intruder fresh or after a sabbatical. This is an extremely hardcore, skill-based first-person shooter, and it forces you to think differently than other modern shooters. If you’re a Call of Duty player, you’re going to need to change your play style to succeed here. Intruder also tries developing into something new here as well, despite doing little to push itself beyond what it’s always done best. Intruder modifies old maps to keep veterans on their toes, and introduces official new modes that encourage different play styles for the first time in almost 15 years.
For the uninitiated, Intruder is a small-scale, team-based first-person shooter with permanent death. When a guard kills an intruder planting explosives in a match, or a guard escort swallows a sniper round in a mission, the victim is dead for good and doesn't respawn until the next round. As such, players on both sides must exercise skill and care. The objective, meanwhile, gives everyone a purpose. Of course matches end when everyone on a team is dead, but a clever and coordinated Intruder team will give the guardsthe slip, and complete their objectives.

Pieces of the Intruder formula are dated at this point, but the superb heart and soul of Intruder is timeless. Teams are small, guns are lethal, and rounds are short. There's an addictive just-one-more-round quality to it, because there's a constant desire to do better than last time, to earn a satisfying kill, or to win in a new way. Call of Duty and Battlefield vets will wonder why they can't sprint to escape enemy fire or look down the iron sights to improve aim; Intruder players will feel like they walked into their redecorated home. Certain map redesigns will catch hardcore fans off guard, but the changes are for the best.

Even in the face of genre evolution, Intruder doesn’t care to adapt. Intruder is so dedicated to Intruder's aging ideals despite market and trend changes that it brute-forces its way to success. Part of what makes it such an engaging competitive game is that killing in Intruder requires a wholly different skill set than other shooters. Everyone is limited to what they have and can see, with little room for character modification or on-the-fly advantages. Running and gunning is a useless play style, to the point that someone standing still is more likely to score the kill. Walking, crouching, or standing are your best bets to reduce the inaccurate spray of machine-gun fire.
Consequently, killing in Intruder feels good. There's a sickening sensation to dropping someone dead because you know they're not coming back. It's also satisfying knowing you used limited resources to play smarter than your victim. If players aren't watching corners, providing covering fire, or using smoke grenades, they're more likely to take a headshot from a more delicate and patient triggerman. The desire to experience that distinct feeling is a strong motivator to keep playing, even when you're getting steamrolled by an obviously better team.

Sadly, noone plays this game so none of that matters.