Ok here is what I came up with for Castor/Pollux skill wise.
Passive: Gets a boost of AP when changing between the two.
Q: Castor: Heals target friendly Pollux: Launches a fireball at an enemy (yeah basic I know but come on...minion Yordles!
W: Castor: Target champion gains increased attack and movement speed. Pollux: Slows target enemy placing a dot on them.
E: Castor: A wave of light flows from Castor removing any snares and cc from friendlies Pollux: A wave of dark energy pulses from around him dealing dmg to any enemy around.
R: Switches between Castor and Pollux giving them a shield absorbing any type of dmg for a short time.

I tried to keep the skills similar between the two since they are twins. Just one helpful the other not so much.

While a few of these concepts show some sure promise (beholder and rock rhino in particular), isn't this what the Player Concepts board was created for?

I absolutely LOVE the concept idea of Yordle twins. Would be a very unique and awesome set of champions.

So like Riven, Quinn's kit revolves around the combo from her Q. However, Quinn is more single target intensive. Without any heavy CC she has to rely on pure damage to out trade the enemy, but a well timed dash and knockback can quickly set up an unwary opponent for her teammates. Quinn is all about catching your enemy off guard and then beating them to death with your fists.

Quinn: The Ionian Avenger

Stats
Health: 414 (+86)
Health Regen: 10 (+0.8)
Mana: N/A
Range: 125
Attack Damage: 55(+3.25)
Armor: 15 (+3)
Magic Resist: 30 (+1.25)
Movement Speed: 320

Abilities
(Innate) Overwhelming Force
Dealing damage with Quinn’s abilities mark enemies with a debilitating injury for 4 seconds. The third injury received by a single target consumes all three injuries and deals 10/14/18/22/26/30 physical damage before reducing armor by 3/6/9/12/18.

[Q] Banishing Fury
Range: 260
Cooldown: 13
Physical Damage: 35/60/85/110/135 (+70% bonus AD)
Knock Back: 325
Skill Description: Quinn lunges towards the mouse, dealing powerful martial blows with each strike to the nearest enemy within range (prioritizes champions). This ability can be activated a second time within 4 seconds and then a third time within 4 seconds. The third strike is a roundhouse kick that knocks back the enemy if one is struck.

[W] Kinetic Power Palm
Range: 125
Cooldown: 8/7/6/5/4
Physical Damage: 35/70/105/140/175 (+100% bonus AD)
AoE Radius: 200
AoE Damage: 25/30/35/40/45%
Skill Description: Quinn’s armor charges a shockwave of energy as she smacks target enemy, dealing damage directly to the target and reduces damage to all nearby enemies.

[E] Punishing Grasp
Range: 450
Cooldown: 10/9/8/7/6
Physical Damage: 50/80/110/140/170 (+80% bonus AD)
Skill Description: Quinn dashes forward for a grappling throw, pausing at the first champion she comes in contact with and dealing damage. If the ability connects she and the target champion switch places.

[R] Safety Override
Cooldown: 75/60/45
For 15 second Quinn’s armor goes into overdrive, exceeding all power regulations. Quinn gains 20% more attack damage and movement speed. She is also granted the ability to cast Critical Mass once for the duration.

Critical Mass
AoE Radius: 600
Base Physical Damage: 80/120/160 (+60% bonus AD)
Maximum Damage (75% health or lower): 160/240/320 (+120% bonus AD)
Skill Description: Quinn’s armor exceeds its maximum energy output, sending an explosion of damage to all enemies around her. This attack deals up to 100% more damage the closer opponents are to 75% health or lower.

Terradon would be so awesome... nice drawings

As someone who would also love to work for Riot's design team, I wish you good luck on getting noticed with your awesome drawings =)

duo-yordles op nerf plz riot

Really liked the whole Quinn concept. Matches perfectly with what I had in mind for a new champion.

Well done

These are sweet keep drawing man. I wanna see more