With the new tank updates, I felt inspired to share some of my own for the rock man.

P: Granite shield - Malphite generates a shield for (9/12/15/18)% of his max health every (25/22/19/16) seconds (at levels 1/6/11/16).

Pillars - Malphite occasionally generates pillars (about 75 units in size {75%the size of a teemo}) between him and his enemies. These pillars act as impassable terrain and interact with his abilities, destroying them. He can have a maximum of 3 pillars up at any one time.

Q: Seismic shard - malphite sends a shard of earth in a target direction (shorter than current q range) dealing damage to all enemies hit. The shard leaves behind a crevice that slows enemies that pass over it, and stuns enemies that dash over it.

Pillars- if seismic shard hits a pillar, the crevice grows in size and slows more.

W: Rock hard - passive: malphite's armour increases by a percent stacking up to x times every time he takes physical damage.

Active: after a 1.5 second delay malphite generates a pillar at a target location.

E: Ground slam- malphite slams the ground, dealing damage and reducing the attack speed of nearby enemies.

Pillars- if this ability hits a pillar, it collapses away from malphite, stunning enemies hit instead.

R: unstoppable force- First cast: malphite charges for a minimum of 1 second to a maximum of 3 seconds increasing the range, damage, and cc of the second cast.

Second cast: malphite charges to a target location, dealing damage and knocking all enemies hit into the air.

Pillars: if malphite hits a pillar, it is destroyed leaving rubble which slows enemies who pass over it in an area. The size of the area increases based on the distance of malphite from the pillar.

Note: these are just ideas, they are in no way intended to be balanced in this form, but are just a brainstorm for updated alphorn abilities. The damage, dealings and cc would need to be different than his current levels of cc.