Does anyone have any VALID tips against Ahriman that doesn't involve some kind of abuse or rush? I'm stuck at the level 40 ahriman in the boss gauntlet in Kyoto and I can't do enough damage to kill him before he kills me 4 times, and I have no clue how to dodge his attacks, they seem unavoidable, especially as there is little or no indication to what variation of attack he'll use.

75% of the time he'll use his lightning based attacks, which you have to block in order to avoid getting killed
The other 25% depends on how far away from him you are, if you're within melee range he'll tilt upwards for a few seconds and release gas, but if you're at firing range he'll shoot seeking orbs which I believe you have to try very hard to dodge otherwise they're an OHKO