Demnogonis Saastuttaja
Magister
I think Arkham Horror really gets boring after a while because it's so easy, and the various add-ons just add a bunch of stuff. A better co-op game is Doom, because it also has a GM. There's experience points, new skills, lots of guns, ammo mechanics, different monsters with different abilities, descriptions of many of the rooms the GM has to read... Just tweak what doesn't work for you, we put a cap on player armor to 3 because with more they'll never die.
Another charming co-op game is Lord of the Rings. Sauron is a black wooden piece with a red dot, and he's coming for you. It's definitely harder than Arkham Horror at least, and I like that it doesn't have a big bunch of crap. It's just simple fun.
Also if you're a fan of Paradox games, try out Struggle of Empires. http://boardgamegeek.com/boardgame/9625/struggle-of-empires Even though it looks really boring, it's mechanically interesting, it's not really like any other game I have played.
Another charming co-op game is Lord of the Rings. Sauron is a black wooden piece with a red dot, and he's coming for you. It's definitely harder than Arkham Horror at least, and I like that it doesn't have a big bunch of crap. It's just simple fun.
Also if you're a fan of Paradox games, try out Struggle of Empires. http://boardgamegeek.com/boardgame/9625/struggle-of-empires Even though it looks really boring, it's mechanically interesting, it's not really like any other game I have played.