This is the first time I've ever tried something like this, so, here goes!
K, for those who don't know Boxhead 2play, search it up in the bar thingy, but it is so great I'm not expecting much people not knowing what it is. Alright. I've got tips for 2 spots, as well as a couple of tips for the whole game. 1 is Boxy (big and small)
The Big Boxy is what I'm mostly referring it to. It is the most underrated of the maps in the Rooms. So, there is a large room with 2 sides with Zombies pouring out both ends. (Remember- always, always ALWAYS put it on nightmare and go into shotgun- then waste them away.) There are barrels on the sides of the middle which get irritating at times, so I suggest taking your shotgun, pistol, uzi or railgun to blow the up while taking a few Zombies or Madelines (My friend and I name the Devils after my cousin, don't JUDGE ME) in the process. After in which you must take out your shotgun (remember: always put it on Nightmare so you start with all the weapons and upgrades) and try to survive. There are many boxes, so it's hard to run out of ammo, and you know you have a bunch of backup weapons as well. Tip: Never use the rocket launcher if you're planning to submit your high score. It's useless, it kills lots of zombies, yes, but its friendly fire range is ridiculous. Also, never set up traps on any levels. The more the bar thing is up, the more points you get after each kill. If you want a score of 76 mil, you can't get 100 points per kill. The Boxy is potentially harder than the big one, since it's very cramped, and zombies would easily swarm you. The Big Boxy is easier to maneuver around. My final tip for the Big Boxy is to go to one area and take them out there, wait for the zombies to go to you from the top or bottom and then turn and waste them all. As for Boxy- try and keep the barrels there, and use an Uzi to waste most of them, then shotgun once they overwhelm the defences.
My second is the Tight. Man, is this one fun on 2 player. You can get creative and survive a long time, since it's so easy- but my strategy for being alone is to- you know the spot at the bottom- well, get to it right away- after taking your shotgun and getting the rest of the upgrades (need I remind you, I'm speaking of it when it's on nightmare.) then running into the thing. It's easy to defend there, since there is only one way in and one way out- so zombies must funnel their way in, and you can defend with a pistol- but when 2 Madelins (Devils, I'm still asking you not to keep JUDGING PEOPLE) go in, you have but a small problem. Taking out your Uzi and blowing them all away, then turning to your pistol. When your uzi runs out, use your shotgun, and after that your railgun. There's a box in the small room, so you can get a refill every minute. Some can go to the second room near the top and fill the spot that the zombies can flank you in with walls or barrels, but I don't see it as a good idea as the other one- but still, it'll work just as well. Maybe if you're on 2 player you can go on each side, and get more points. Tip: It's a bad idea to use explosives of any kind. Charges and mines are pushing it, sometimes it takes a while to set them down and you have to kill all but one zombie to set it up- and after the zombie horde a group of Madelins go in and they can kill zombies. Grenades are okay, in some levels at least- but not for me.
An extra tip for the Maze- you start with firing your shotgun at the zombies at the very right spot where you start at until your almost out or have all the upgrades. then you can go on a lot easier. Another tip: limit your arsenal. And not the way you think. When you practice or try to get better, try weapons other than a shotgun, like an uzi or a pistol. Some levels, though, like the tight 2 are impossible to use with just pistols, but still, to make yourself better you have to make due with what you have.
K, you guys can put down your stuff with other maps down the Forum or the Comment section, I don't care.
P.S. Sorry if it's messy, it's 11:14 PM right now.
