Being an Ex Driver i know how to take down a mau. First of all don't think of defeating a mau, all you need to do is pester it and the driver will either run away or get out. Also, if you're under lvl 30 don't even think about taking on a mau, you're just going to waste pots. If you see one, just run. Now if you're a level 30+ then you can start taking on maus. First thing you will need is enough potions. You should always be carrying some anyway for leveling. You will need to look at the mau and determine if it is a melee or ranged mau and how much Mau PT the Driver has. On melee maus, you can tell if the driver has less that 15 pt if he/she doesn't have boosters and is still using fists. On ranged, if the driver has less than 15 mau, he/she will have vulcans as weapons. For 15-30 PT a melee mau will have a booster and a ranged mau will have flamethrowers. for 30-45 PT A melee mau will have sword-fists and a ranged mau will have rocket launchers. at 45+ melee maus will have a net launcher on its shoulders and a ranged mau will have a debuffing rocket launcher on it's shoulders.
Maus under 45 PT you can solo. The trick is not to kill it but to make it go away or annoy the driver to come out. The key thing with maus is that it takes TONS of money to repair, about 500k Dalant for full repairs. So most lvl 30's can do dmg in the 200's - 500's. This is enough damage to make a mau run away once it realizes it can't take you down because you keep on potting. If you're a ranged user, just kite (run and gun). Melee maus over 45 PT are annoying because they can net you down and you can't run. Also, force users do the best damage to maus.
Now if there is a group of maus you have to look for one thing, if one or more of the maus can net you. If theres a netter, run because if he/she nets you and they all attack you at the same time, you won't survive.
Now the best way to destroy/blow up a mau is to gang it. When a mau loses all its hp, it will explode and the driver will need to buy a new one. (one million credits.) The most effective way to take down one mau is to have one tank hit it and let the ranged users shoot from afar. Force users will do the most damage.
I'll write a faq later on taking on groups of maus, but thats pretty tough. Remember, the key to defeating maus is potting and doing damage till it gets fed up and runs away (if you're soloing). You can then chase after it until the driver gets out so you can kill him/her or just let it go.
Continuation - Fighting back against a group of MAUs:
Well honestly, defeating a group of MAUs is very tough. If you're soloing and near some guard towers, run toward them. Theres no way you can solo a group of maus. The most effective tactics I've seen used against me were mobbing and mobbing with force users. You will need a good organized party of people lvl 30 and above (Preferably mostly force users), and plenty of pots. The key to defeating the group of MAUs is to scatter them. When MAUs attack one target together, it's a sure kill. So you have to seperate them. The best way to do this is to attack different maus to lure them away from eachother and toward an ambush party or something. This is probably too organized to be used regularly. A more practical thing to do is to gang catapults first. Since they can't run, they're easy targets for range and force users. Once the catapults have run away or the pilots have bailed, focus on the goliaths. These are more dangerous since they can keep up with their boosters. The party is going to have to target one MAU and keep hitting it so it has no choice but to leave. Keep doing this till they get fed up. As long as you keep the MAU group unorganized and confused. They won't get very far. Remember, you probably won't be able to blow up the mau, but getting the driver to bail is the next best thing. Concentrate your fire on one mau at a time.
Edit:After playing NA/UK beta, I have to really stress that if you're being chased by more than 2 melee mau, run. I'm a level 35 Accretian gunner with good gear and race leader status. This means that I get a 20% defense bonus + I have intense level 35 armor + a 25% defense bonus from being race leader. Even with all this, when I was netted and hit by 3 melee mau, my hp was brought down to around 100. Two of these mau had around 40 unit pt and the other one was pretty low. Considering all of this, if you see more than 2 melee mau chasing you, don't bother trying to confront them. If they all target you, you're dead.
Additional Info
MAU are constantly upgraded as the MAU players level up, all the way to Lv 48. This means their armor gets tougher and their damage increases and they can store more ammo. At Lv 40 or higher, the MAU players can access the Black MAU (or BMAU). This version has meaning looking graphics and blade arms (Goliaths) and vulcan arms (Catapult). MAU armor is tough against normal attacks, but it takes high damage from skill attacks (this includes melee skills, range skills, Accretia gunners in siege mode, and all offensive force skills).
MAU also have limited accuracy. If you manage to achieve high levels of Dodge/Avoidance, you can pretty much dance in the middle of a MAU party without getting hit, but be cautious because the Catapult debuff can reduce your dodge by -30 for 10 seconds.
