let's talk about some popular matchups for malzahar in the mid lane. i'll rate the difficult from 1(eaisest) to 5(hardest)
Fairly easy match up, might be dangerous early game if you keep eating her poke and you get charmed. If you stay within your creeps so you're immune to charms, you should be able to out push her. After 6 she will never be able to all-in you because you can just 1 shot her with your W+E+R combo (even if she dodges your Q with one of her ult charges).
this is a bit tricky. She will just try to afk push, so you will have to do enough damage early game to her so that she won't be able to do that. After 6 is also really tricky because when you have your ultimate you beat her, but when it's off cooldown she beats you. So try your best to keep the lane even and always be trying to harass her and zone her when you can. This is only hard if you make it hard for your self by not punishing her early.
You can completely crush evelynn in lane, you can just pretty much zone her and she won't even be able to farm. She'll most likely just end up roaming a lot, so make sure you buy a pink everytime you go back, so you will know which direction she will be roaming off to.
this match up is surprisingly very easy. Don't eat his ranged Q+E harass, you're perfectly fine if you stay a bit behind minions and permanently push using your E. If he ever all-in's you, you will be doing a LOT more damage to him than he will to you, especially after you have your ultimate. Jayce pretty much have to rely on landing his ranged poke to do anything in this lane.
easy lane, karthus (especially solo queue karthuses) cant apply enough pressure in lane against you. You have a free farm lane, can easily push to tower and roam. you can give him hell when he's farming under tower, just make sure you have at LEAST one side warded and stick to that side. You can stop his ultimate with your ultimate so staying in lane with him isn't a bad idea.
You have to make sure your voidlings are always up. As long as your voidlings are up you can be auto attacking him and all he will be able to do is Q you and back off. If you can get a big enough lead from early game before level 6, you'll be fine going into late game. However, after 6 he will completely crush you.. Because of his magic reduction passive and his annoying silence he will give you hell after level 6. My advice is to get a lead early, and don't throw it.
easy lane. Do NOT isolate yourself, everytime he comes up to auto attack a creep you use your E on him and auto attack him out of lane. He will be forced to farm with his spikes, and he will not be ever able to all-in you after 6 because you will just kill him using ultimate.
probably one of the most annoying match-ups for malzahar. Her range is stupidly strong and it's hard to out push her either. If you ever get binded you will get chunked if not die... so my advice is farm until 6, and roam and make use of your ultimate. Good luxes will not be in range for you to use your ultimate on her.
another easy lane. Nidalee is weak against heavy pushers, and malzahar is one of them. Another thing is she has 0 cc so even if she gets ganks, she will still have not much threat. After 6, she can never go cat form or you can just.. ult her. easy!
an even match up. She will pretty much try to use her annoying Q pokes at you, but it's pretty easy to dodge them. I don't recommend wasting your mana too much on using your spells on her because she just shields most of the damage. Just keep the lane steady, push using E, and look for a possible opportunity for a kill after level 6.
You outdamage tf so hard in lane that you can get gold carded + wild carded and still outdamage him with just your E. Pressure him hard in lane, but always watch out for jungler ganks because his stun card + jungler is scary. I recommend starting out with at least 1 ward against a TF. Remember you can also stop his ultimate with your ultimate as well.
unless zed all-ins you when you blow all your cooldown, you can fight him. Zed's all about outplaying and doing all-ins using ultimate but.. it's hard to outplay 2 target skills and 2 aoe spells. Easy match up! I also recommend getting seeker's armguard a bit earlier, and zhonya's first big item.