[Rework] Malphite, the Walking Volcano

This is just a skill set I thought of so nothing to major. I went for more of a Volcanic theme than just a Mountain theme. If I were any good at drawing I also would have put my vision of him onto paper, or for that matter whatever programms people use for drawing nowadays, but sadly I'm not.

Well then here we go:

Malphite, the Walking Volcano

(Passive) Magma Mantle

Malphite constantly produces magma which leaks and solidifies periodically, granting shields (4% max health) every 4 seconds when out of combat up to a maximum of 3 shields. Damage from minions or non-epic monsters resets the recharge timer to 2 seconds.

(Q) Volcanic Bomb (Mana cost: 55/60/65/70/75; Cooldown: 10/9.5/9/8.5/8)

Malphite shoots a Volcanic Bomb from his left arm, dealing 70/110/150/190/230 (+75% AP) magic damage to the first enemy hit. If the first enemy hit is a minion or monster the rock shatters, dealing the same damage to the enemies behind it. If a champion is hit the champion is slowed briefly for 50%/55%/60%/65%/70% and the "Bomb" bounces behind him, which then can be picked up to reduce "Volcanic Bomb"'s cooldown by 2 seconds and replenish one of "Magma Mantle"'s shields. Rocks that dont hit anything can also be picked up but only grant the cooldown reduction and not the passive shield.

(W) Eruption (Mana cost: 70; Cooldown: 8/7.25/6.5/5.75/5)

(passive) If a "Magma Mantle"'s shield is destroyed by any means Malphite leaves igneous rocks behind for 4 seconds, which deal magic damage to enemies walking over it for 20/30/40/50/60 (+10% AP) per second and slows them for 15%. Destroying multiple shields at once with "Eruption"'s active effect does NOT increase this passives damage but the area in which the igneous rocks are left behind.

(active) Malphite causes an eruption, dealing 50/80/110/140/170 (+30% AP; +15% bonus armor) magic damage around him for 1 charge of his passive. For every aditional charge of his passive the damage is increased by 40%. (30% increased damage against minions and non-epic monsters) The passive shields are used up in the process.

(E) Rock Slide (Mana cost: 50; Cooldown: 16/15/14/13/12)

Malphite charges forward, dealing 50/80/110/140/170 (+50% AP) magic damage to all enemies hit, stopping at the first enemy champion or terrain. If an enemy champion is hit you can charge again in the next second in a 120° angle while the enemy champion is stuck onto you. Charging together with the enemy champion into terrain deals 50% (+4%/5%/6%/7%/8% max health) extra magic damage and knocks him up for 1 second. If you dont charge him into terrain you push him away instead without dealing additional damage.

(R) Continental Catastrophy (Mana cost: 100; Cooldown 150/135/120)

Malphite accelerates his magma production, granting him 1/2/3 of his passive shields (which can excede his normal maximum but only last 6 seconds if doing so), while he starts pumping it into the ground for 2 seconds, causing a traveling tremor in a big cone shaped area, dealing 100/200/300 (+50% AP) magic damage and unleashing a massive wall of erupting magma for 4 seconds at the end of the earthquake which act as indestructable terrain. Enemies inside the earthquake area are slowed for 15%/22.5%/30% while Malphite is sped up for 10%. If an enemy dashes through the eruption or is slammed, pushed or pulled into/through it by displacement abilities the eruptions deal 100/160/220 (+30% AP) magic damage (this damage can only be dealt once). Standing where the magma erupts when it erupts also deals the 100/160/220 (+30% AP) and always pushes the enemy between the wall and Malphite. While pumping the magma into the ground Malphite cannot be disabled.

Context to the "massive"ness of the magma wall. It's supposed to be broad enough to cut of an entire lane and the intial tremor has a range of about Nami's Ult. I also played with the thought of increasing its width with every level but if I intend his ult to be of the charging kind it would be to easy for the enemy to escape even without escape tools presuming his level 1 ult cant cut of an entire lane.

Feel free to leave suggestions in the comments.