[Champion Concept] Terra, the Gaia Manifest
Let's face it - while Malphite can be played AP, there is no "true" Earth/Rock Mage in the League (and no, Azir's sand doesn't count!). So, well, yeah. Let's go!
Note: I'm aware that the numbers on the skills are badly balanced. This is more of a kit overview more than anything else, and numbers can be changed accordingly.
Terra, the Gaia Manifest Attack Power: 3/10 Defense Power: 5/10 Ability Power: 10/10 Difficulty: 6/10
Health: 504 - 1794 Health Regeneration: 5.4 - 14.8 Mana: 330 - 1206 Mana Regeneration: 6 - 19.6 Range: 550
Attack Damage: 55 - 110 Attack Speed: 0.625 (+0% – 23.1%) Armor: 19.9 - 74.4 Magic Resistance: 30 Movement Speed: 335
Abilities
Innate: Stonehenge Up to 5 sharp stones appear around Terra once every [14/13.5/13/12.5/12/11.5/11/10.5/10] seconds (affected by Cooldown Reduction). Each stone increases Terra’s Armor by 4. Enemies that touch a stone are dealt [30/45/60/75/90] (+0.2 AP) Magic Damage. Enemies cannot be damaged by this effect more than once every 4 seconds.
I really liked Xerath's old passive (AP -> Armor), and I thought it'd fit really well on a stone mage (with a stone shield and everything). However, Riot doesn't like Stat -> Stat passives, and have been phasing them out little by little (there were quite a few before, but now only 
and 
remain). So instead I made it a sort of ammo resource/damage trade-off for her E - so she has to choose between damage or tankiness. Sure, the recharge rate is pretty low (with 40% CDR, it's 6 seconds per stone) but that's a given lategame.
Q: Granite Crush [80/80/80/80/80] Mana | [14/13/12/11/10] sec. Cooldown | Range: 850/200 AoE
Fires a large boulder in target direction, dealing [60/100/140/180/240] (+0.6 AP) Magic Damage in an area around its landing point or around the first Champion hit. If it stops at an enemy Champion, they are slightly knocked back.
Somewhat generic ranged Q spell - it's functionally identical to Gnar's Mega Q, in that it only hits an area instead of a line. However, it doesn't stop at minions, only Champions, and it knocks them back slightly to boot (think Maokai Q) instead of Slowing. The AoE is smaller than Gnar's, though. This spell plus her W are both strong setup tools for her Ult.
W: Fissure [70/70/70/70/70] Mana | [12/11.5/11/10.5/10] sec. Cooldown | Cast Range: 750 | Line Length: 600
After a 0.3 second delay, Terra opens up a horizontal rift in the ground that lasts 4 seconds. Enemies that touch the rift are dealt [80/100/120/140/160] (+0.6 AP) Magic Damage and are slowed by 30% for 1 second. The slow is refreshed as long as they stand on the rift. Cannot damage an enemy more than once per Fissure.
Fissure aims like Anivia's Wall/Malzahar's Q, but functions more like Rumble's Ultimate in that it creates a line slowing zone. Damage occurs only once per cast - as such, coupled with the low overall damage increase and CD decrease per level, means that this is a one-point wonder until lategame.
E: Stone Barrage [30/30/30/30/30] Mana | [2/2/2/2/2] sec. Cooldown | Range: 900
Terra fires one of the sharp stones that circle around her in target diraction, dealing [24/36/48/60/72] (+0.18 AP) Magic Damage, reduced by 10% for each enemy hit, down to a minimum of [9.6/14.4/19.2/24/28.8] (+0.072 AP) Magic Damage (minimum of 40%). Cannot be cast if Terra has no stones available. Maximum Damage with 5 stones: [120/180/240/300/360] (+0.9 AP) Minimum Damage with 5 stones: [48/72/96/120/144] (+0.36 AP)
While Q is better for the nuke damage early game, come late game, this becomes Terra's bread and butter damage and farming tool. I actually kind of copied this skill from Irelia's ult, reducing it's spammability and overall damage and but heavily increasing it's usability.
Note that this spell's damage decreases when passing through enemies - if you hit 6 minions before it lands on an enemy Champion, it doesn't really hurt much. Also, using this spell essentially reduces her Armor every cast. As such, she has to consider divers during teamfights, and whether she should hold on to some of the stones, or just throw them all out for maximum damage.
R: Earth Chant [100/100/100] Mana | [100/90/80] sec. Cooldown | Range: 1250/200 AoE
Terra summons 4 stone pillars in a line that erupt from the ground after a 0.5 second delay between each pillar. They deal [200/300/400] (+0.70 AP) Magic Damage and knock up for 1.5 seconds all enemies caught in their radius. Enemies cannot be damaged by more than one pillar, but the knock up can be reapplied if circumstances permit.
I took inspiration from Nami's Ult, Braum's Ult and Nautilus' E and Ult to make this one. The range is MUCH smaller than Nami's (2750!), but it's functionally similar to it and Braum's Glacial Fissure. It's a lot less wide compared to Tidal Wave, as well, but deals more damage.
As you may have noticed, Terra's very much a teamfighting mage. While she can setup kills in 1v1 situations by herself, her Ult lacks the upfront burst that other Mages can boast, having a relatively low AP Ratio and base Damage compared to, say, Tibbers. Also, enemies can only be damage by one pillar (though they can be juggled with the knockups - I don't know how that could happen, but it's a thing)
So that's it, I guess. The kit is still something I threw together rather quickly (with only the E taking some time to think of - my first idea was more like Vel'Koz's fissures, but then I realized it'd be too similar to Terra's W), so they can be changed if they're too OP/UP/Weird. Feedback is appreciated. Here's a jamming Cubone for your time.
http://38.media.tumblr.com/tumblr_lqp661V9ZO1r0mhfro1_500.gif
