highest defense gear you can get. i went with behemoth's mantle +1, SH+1, those Defense Bangles from that Beetle etc. Eat a taco and be sure to protect 4. Maat should have difficulty hitting you for more than 10-15 with phalanx on.
This was as a Level 66 Tarutaru.
If you are level 70 more gear will open up to you and you could actually just do a full RDM melee.
Sleep him when he chainspells.
It's one of the easiest Maat fights if you don't try to be lolBLM and remember that you are a RDM.
LV70 (or 70+ for Beyond the Sun) can also sleep TP and icarus wing for double weapnskills to beat him time. Not really worth it if you don't have Savage Blade.
Otherwise just melee him and drink potions for HP til he 2hrs
Sleep him when he 2hrs (macro in gear for this). Try sleep 1 and then put sleep 2 on it about 15 seconds later. Run away.
Use any meds you wanna use and wait for him to come in range (he'll start casting a random spell so make sure you rebuffed and put blink up to). open up chainspell and spam stone3.
When your MP is about to be around 125, start spamming sleep2 til it sticks.
Cure, convert cure. and start casting more stone3s. should be able to do this before chainspell wears.
meleeing him til he does his 2hr makes him significantly easier and his asuran fists shouldnt break double digits if he uses it (if not then you are doing something wrong your defense should be like 450+ and you have phalanx on)
Damage Reduction Gear is also pretty decent.
If you don't have sword skilled you have to do it the gimp way that many people die on even at 75 which is trying to fight him as a gimp black mage. I beat him on RDM66 Tarutaru, with absolutely no problems using this method. The fight wasn't even close. His best Asuran Fists (he did it twice) was something in the 70s. He would have to hit me for a minute or weaponskill just to break stoneskin because he'd normally hit me for only around 10ish. A good stoneskin will last a while.
Running up and sleeping Maat before you buff can prevent him from buffing. I did this and it worked great. Was able to buff and I started casting enfeebles til he woke up.
The people here who say Asuran Fists do 200-300 damage were most likely tryign to beat Maat in mage gear. Some people report damage up to 400+. Some people take as much as 100 damage for a regular hit. This kind of thing is fine for a black mage. but if you want to be a red mage, start acting like one and and buff yourself up.
Also, enspell on Maat. I went with day of the week enspell which I think was earth's day so it was enstone
