Alexander, the Chess Master(Mechanically Difficult Mage)
A champion sort of similar to Azir in style and gameplay. Attack: 1 Defense: 3 Ability: 9 Difficulty: 10
Lore: Alexander was always a talented kid. He was incredibly smart and could solve any problem you gave him in a matter of seconds. He took up chess as his hobby, and was easily able to beat everyone he matched up against. He soon turned this into his life, and has been undefeated since he started. One day, however, he found a strange stone in the forest. When he touched it, it allowed him to bring chess pieces to life and use them to help fight in the army. Once word of this spread, he was taken away to join the League of Legends.
Passive: Chess Board- The map is divided into squares when Alexander is in the game. He can only use his abilities in the middle of the squares. When he uses his abilities, he dashes forward a short distance in the direction he's facing. He can ride the chess pieces by right clicking on them(and is still able to cast spells), and he can move the one he's on and the ones he's not on by clicking and dragging(2 second cooldown). The chess pieces last for 8 seconds.
Q: Pawn- Alexander summons a pawn on a square after a 0.75 second delay, dealing 50/80/110/140/170(+40% AP) magic damage to enemies in that square. The pawn can move 1 space at a time in any direction except diagonally, dealing 25/40/55/70/85(+20% AP) magic damage to enemies that are in the new square and slowing them by 30/35/40/45/50% for 2 seconds. Cost: 50/60/70/80/90 mana Cooldown: 12/10/8/6/4 seconds Range: 750
W: Bishop- Alexander summons a bishop on a square after a 0.75 second delay, dealing 60/100/140/180/220(+55% AP) magic damage to enemies in that square. The bishop can move diagonally 1 or 2 squares at a time, dealing 30/50/70/90/110(+27.5% AP) magic damage to enemies in the new square(doesn't deal damage if it passes through them). Cost: 60/70/80/90/100 mana Cooldown: 13/11/9/7/5 seconds Range: 750
E: Knight- Alexander summons a knight on a square after a 0.75 second delay, dealing 40/60/80/100/120(+35% AP) magic damage to enemies hit and stunning them for 1/1.1/1.2/1.3/1.4 seconds. The knight can move 3 squares in 1 direction and 1 square in another at a time, dealing 20/30/40/50/60(+17.5% AP) magic damage to enemies in the new square, stunning them for 1/1.1/1.2/1.3/1.4 seconds and marking them for 7 seconds, making them unable to be stunned again by Alexander for the duration. Enemies that the knight passes through take no effects. Cost: 55/60/65/70/75 mana Cooldown: 12/10/8/6/4 seconds Range: 750
Ultimate: Queen- Passively makes it so that when Alexander summons a chess piece, all active chess pieces remain for 1 extra second. When activated, Alexander channels for 2.5 seconds and then flies quickly on a queen to any square on the map, dealing 200/300/400(+80% AP) magic damage to enemies he passes through, reduced by 10% for each unit hit(minimum 40%). Cost: 100/125/150 mana Cooldown: 200/160/120 seconds Range: Global
Example Item Build: 
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