You can learn from the sounds and speed of enemies charge up what they're going to shoot. After a while you can dodge everything by jumping or ducking at the right time, aside from somethings like splinterguns or hyper pulses. But if you keep your armor in decent shape getting caught off guard by those things shouldn't even really hurt you.
For enemies that dodge or reflect, you should use more effective weapons. Make sure you pick up some hacking skill and combine weapons. Spread rockets are effective against dodgers from half-screen range (don't shoot at something that reflects shots though), and the plasma cannon is awesome against pretty much anything (except the giant annihilators, the normal shocksplinter is actually better for them). The machine gun is, IMO, kinda worthless, and the splintergun isn't much better. I'd rather use its ammo for the Buster Gun, which can really chew through individual enemies without much trouble if you have good attack.
And against Asha make sure you're using the proper weapon (Shotgun or Buster Gun), otherwise you'll never beat him
As far as difficulty goes... well. I have a kinda low opinion about most games' difficulty nowadays. Iji's really not a very hard game. It's reasonably challenging and there's few cheap tricks that can't be avoided with some foresight.



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