It's really impressive how well this game manages to accomplish its only goal: raw, blood-pumping aggression. The glory kills, which are used to give the player mini-rewards for good play, are a particularly genius mechanic. It's really underestimated how valuable a few seconds of being able to catch your breath and think about your next move are while playing as a glass cannon character in a high-speed action game, and the intensely gratifying animations certainly don't hurt. My gripes with this game come from the parts that feel as though they were implemented to bring the game up to speed with modern gaming standards, mainly the upgrade system and the map used for exploration. I understand the idea was to throw in some non-action elements in order to keep the game from becoming too repetitive, but c'mon, it's DOOM- no part of it should require a menu.