[quote name='slowdive21']This isn't meant to be trolling, but are the expansion packs worth it? I played through the game once and got board with it. I have never played on multiplayer either. Is that more fun or is everything in the exact same place as it is in the regular campaign?
It seems like all I do is check the same crates and get slightly better weapons. I also have trouble finding out what weapons are better than others. It seems like the ones you can sell for the least are actually the best weapons for my character.[/QUOTE]
Two of the expansions are worth it: Zombie Island and Fort Knoxx. Robot Revolution is meh, and the Underdome is just a frustrating experience (see below). Playing co-op makes it a whole new game. The enemies become more difficult and drop better loot. Strategy really starts to come into play when you get more people playing and this is when the game becomes extremely fun.
Everything is in the same place, but as I said, the enemies are harder. My friend and I have played it so many times that we go through the campaign by speed raiding. Basically, we go in areas and tactically clear them as fast as possible. Sometimes we also play using only certain types of weapons and we also try to switch up and use different classes.
If you want better weapons, you can farm the New Haven area by running around and hitting all the chests then saving and reloading. Check YouTube for some videos on the quickest route. If you do that for 30 minutes or so, you should get some better stuff. Sell all the crap, and check the machines for orange/yellow weapons.
If you get the Knoxx DLC, you can farm Crawmerax for better gear which is easy as soon as you figure out the right spot in the rocks to stand and get a sniper called an Orion that lets you ricochet rounds onto his back. Keep in mind you need acid weapon for the armored worms, electric for the maggots, and fire for the green worms. I can kill him alone with my level 69 soldier in probably 10 minutes or so 85% of the time (sometimes he knocks you off the ledge running to your spot.
As far as telling which gear is the best, rarity is coded by: White < Green < Blue < Purple < Orange/Yellow < Teal (only if you have Knoxx DLC, and only in special chests or from certain enemies). While that order doesn't necessarily equal the best, it is a good indicator. I wont even look at a weapon or item that isn't at least purple.
About the Underdome (didn't want to disrupt my train of thought above): You basically have these arenas where you fight wave after wave of enemies. The enemies are scaled to your level, they give you ZERO experience, and the weapons at the end of each round are shitty at best. There are a series of lower challenge arenas in which you fight 5 rounds with each round having 5 waves of enemies. The larger challenge arenas are where it becomes terrible because it's the same maps as before only you fight 20 rounds with each having 5 waves of enemies, so basically 100 waves of enemies.
During the challenges, if you are alone and you die, you get rolled back a few rounds. If you are with a co-op partner, and one of you dies you get hung up in a penalty cage that you can snipe from. If you both die, you get rolled back a few rounds. To make it even more frustrating, there are mods to each wave. Some examples: enemies move at high speed, enemies have larger magazines, you have no shields, or my personal favorite: vampire, during which you constantly lose health unless you are killing something.
My friend and I did two of the larger challenges with two level 69 soldiers and it took us 5-6 hours for each challenge. Keep in mind we both had insane orange elemental weapons, the most legit shields we've found after 100+ Crawmerax runs (toughest boss, drops best loot), class mods that did team ammo regen and team shield regen, and we held up in the best possible sniping or defensive positions the entire time.