Going through both of the Quake 2 Mission Packs because I've been on a '90s/early '00s FPS kick. Level design is good and the combat, especially in the second MP, is pretty great, but both have that particularly annoying trait of having enemies that just completely kill momentum and are a pain to get rid of. The beta-class Gladiators in MP1, which aren't too tough to fight but just take so long to kill, and those damn turrets in MP2. Shame, I really think the combat in MP2 is fun and quite challenging (by Quake standards) but those turrets are both cheap and annoying a lot of the time.