On the poke rune page, I would swap Manaflow Band for Axiom Arcanist. Malphite doesn’t really need mana if you rush Frozen Heart first item, and that build is actually pretty solid.

Scorch is okay if you want more damage during laning phase, but I always prefer the scaling rune. Even without Scorch, you can win almost any lane without much trouble. I think Scorch is only worth taking against squishy ranged matchups. Against melee bruiser, not worth in my opinion.

Transcendence feels kinda weak and, in my opinion, pretty useless on Malphite. In mid and late game he doesn’t need the extra CDR - his abilities (especially W) already have low cooldowns, and he doesn’t need it early either. Of course it makes some difference, but it’s minimal. In all my games I go Absolute Focus or Celerity depending on the matchup, and I think they’re clearly better.

The rest, the secondary runes, resolve tree + shards are good. I liked them.

About the second rune page: I don’t think Demolish is good on Malphite. He’s not the type of champion who just sits top and pushes towers like Darius or other bruisers. In my opinion, switching to Shield Bash is much better. It gives you a strong advantage in lane trades and also in teamfights later on, it’s actually pretty OP.

While Shield Bash helps you win fights and trades, Demolish only helps with tower damage, and Malphite wasn’t made to be a tower destroyer like some bruisers.

Conditioning and Unflinching are solid. In the secondary tree, I would switch to Axiom Arcanist and the scaling rune. In the shards, I’d replace the CDR shard with an adaptive force shard.

For summoner spells, I always take Ignite nowadays. Since we got free TP, Ignite helps a lot in lane, you can create a big advantage early on.

That’s pretty much it. The rest of the guide is really nice. I’ll test the build later.