My main is Lux so I go mid obviously. But how do I counter Malzahar? Apparently his silence is very long, he spams his abilities and doesn't run out of mana, he's somewhat a good farmer and his combo and ignite just kills me when I have full health any help?

Don't stand in the silence, and stay back from minions afflicted by malefic visions. Lux is great at farming from a safe distance, and her biggest weakness, in my experience, is gap closing assassin champions like Kat or Kassadin, so she should do just fine against Malz.

Let him push and get jungler ganks. There is a reason you dont see morde/malzh/trist in competitive play, impossible to have good lane control

I played this exact match earlier today, malz(me) vs lux. use your circle charge thing to poke me and back away from the creeps that are affected by my vison.

the silence is a longer range than my vision so be careful for that poke.

finally get good ganks, just be wary of wards on the bushes. good luck

Qss. Rush it.

Lux is a great counter to malzahar. I main Malzahar, and my biggest challenges are smart lux players, any for kassadin and LeBlanc.

The key to beating malzy is realizing where his strength is, he's a close range caster. The only way he can get you long range is if you stand near his malefic Visions and it procs onto you from on of your minions.

Lux has a decent range, longer than malzahar. Keep him at bay with your little exploding circle, and if he moves in close punish him for it by stunning him and giving him a good burst.
DON'T stick around after that though unless you're going to kill him, because if you stay close enough for him to use his spells on you, then you'll take a beating.

anyways, I hope that helps!