This is pretty much a small project I've been working on. Ever since the Lissandra patch, I found out that all the pieces (Major Arcana) are in place, and can be finally implemented into a tarot deck.
Discretion: Champion splash arts and the Rune Icon are copyrighted to Riot and its respective employees, I do not own any part of the said artwork other than the layout of the cards. This tarot deck may be copied, printed, edited or redistributed for educational or non-commercial reasons. Renting, selling or using this tarot deck for commercial reasons violates any of the aforementioned stated artwork's copyright, and will be subjected to Riot's discretion. Oh, and mention Yours Truly, Mineko Charat Lucky, when someone asks who made it.
Champions that have already represented an arcana will not repeat again on other arcana, just so to maintain variety.
Alright, time to show and explain what, how, and why the champions represent the various arcana. This will be ridiculously long though, so bear with me.
The Fool
"Yep, that tasted purple!"
Main Choice: Lulu
Reason: Lulu fits a lot of descriptions of a Fool, she may not be stupid, but her way of thought is different even for yordle standards, let alone humans. She thinks outside of the box. She learns faerie magic purely because of her desires. She may be a bit lunatic. She appreciates Nature, and the beauty itself. A Fool's journey, ever since meeting 
Pix. With her absoulte lack of common sense, she is oblivious to other people's thoughts and is unable to fit with other yordles properly.
"A new journey begins."
Alternative Choice: Wukong
Reason: Wukong is a solid contender as well. Born from stone, he's pathless, aiming around endlessly. Until he met Master Yi, and from then on, a new journey begins, to fight skilled warriors.
The Magician
"For my next trick, I'll make your lifebar disappear."
Main Choice: LeBlanc
Reason: Self explanatory.
"Light mage? I'm just an ordinary mage."
Alternative Choice: Lux
Reason: Self explanatory.
The High Priestess
"By force of will!"
Main Choice: Karma
Reason: Karma represents the presence of the divine. Strives to have peace, but will resort to power if required.
"We're all tied to the ocean."
Alternative Choice: Nami
Reason: The High Priestess also represents the sea. It is calm, yet violent as well. Nami's job is basically a "priestess" too.
The Empress
"United, we are stronger."
Main Choice: Ashe
Reason: Married to Tryndamere. She wishes for prosperity, abundance, representing the Empress.
"My true beauty is beneath the skin."
Alternative Choice: Elise
Reason: Queen of the Shadow Isles. Desires for more power from the Spider God. Themes of power, beauty and and satisfaction exists in Elise as well.
The Emperor
"The power... is undeniable."
Main Choice: Tryndamere
Reason: Married to Ashe. Symbolizes Fathering, Authority, Power, Leadership and Experience.
"My destination is absolute."
Alternative Choice: Swain
Reason: Symbolizes Authority, Power, Command, Structure, Egocentrism, Rigidity, Leadership and Experience
The Hierophant
"The way is always the same."
Choice: Zilean
Reason: Knowledge, Discipline, Maturity, Formality and Respect, fits Zilean.
The Lovers
"Charmed, I'm sure."
Choice: Evelynn and Twisted Fate
Reason: There's only one pair of couples that is featured together in a splash, so this is perfect.
The Chariot
"Send me to battle."
Main choice: Hecarim
Reason: Hecarim fits this perfectly, he's a horse, and his symmetrical design fits the Chariot's theme of "split in half".
"Fate has made its choice."
Alternative choice: Xin Zhao
Reason: Chariot also features wings on the rider, and Xin Zhao also fits this in a sense.
Justice
"The scoundrels will pay!"
Choice: Garen
Reason: Demacian Justice!
The Hermit
"Master yourself, master the enemy."
Main Choice: Lee Sin
Reason: A monk living seclusively, hardships in Ionia (self-immolation), trains alone for self-enlightenment.
"I think I might know a relative of yours. No hair... sagging flesh... always going on about brains. Ring any bells?"
Alternative Choice: Yorick
Reason: Lives alone in the Shadow Isles in seclusion. Will someday make himself known to all as Yorick Mori.
Wheel of Fortune
"Fortune doesn't favor fools."
Choice: Miss Fortune.
Reason: Fortune, Ship Wheel, ring any bells? Wheel of Fortune indeed.
Strength
"There is no strength in servitude."
Main Choice: Sejuani.
Reason: Strength always feature a (usually strong) woman and a beast. Sejuani fits this perfectly. In fact she defines Strength.
"They are nothing before me."
Alternative Choice: Shyvana.
Reason: Same as Sejuani.
The Hanged Man
"Just a little bit closer."
Choice : Shaco
Reason: Only Shaco's splashes has him upside down.
Death
"I'll put you... in my book!"
Choice : Karthus
Reason: Grim Reaper.
Temperance
"Shall we resolve this dissonance?"
Main Choice : Sona
Reason: In-between Death and the Devil, Temperance signifies Harmony, Balance, Health, Well-being, Recovery and Healing.
"Balance in all things."
Alternative Choice: Irelia
Reason: Balance, nuff said. The splash art is peaceful as well.
The Devil
"I prepare for what waits beyond. Shall I show you?"
Main Choice: Galio
Reason: A powerful being from Hell.
"Not all angels are good."
Alternative Choice: Morgana
Reason: A Fallen Angel.
The Tower
"Succumb! It's inevitable."
Main Choice: Lissandra
Reason: She's tall (and I mean really tall), slender as a Tower, don't you think? Besides, the Tower is never a good sign, meeting her always spells doom. (All the lores involving the Ice Witch never ends well).
"I will be free."
Alternative Choice: Xerath
Reason: Another strong contender. Should the day he escape from his sarchophagus, Runeterra is over. And he's tall like a tower too.
The Star
"Stars, hear me!"
Choice: Soraka
Reason: Stars.
The Moon
"Chosen of the Moon."
Choice: Diana
Reason: Moon.
The Sun
"Chosen of the Sun."
Choice: Leona
Reason: Sun.
Judgment
"Your time has come."
Choice: Kayle
Reason: Judgment. I mean really, is there anyone else that can fit Star, Moon, Sun and Judgment? Don't blame me for giving extremely short answers.
The World
"Do not deny your instincts, summoner."
Main Choice: Udyr
Reason: The world signifies completion, and is represented by 4 things - Man, Beast, Bird and Fish. Udyr here has Bear, Tiger, Phoenix and Turtle, which covered all four of the symbols. The four completes him.
"Ah, the taste of the Earth, is just marvelous. Life is just wonderful."
Alternate Choice: Cho'Gath
Reason: Cho'Gath ate the World. The destruction of the world is completed. Time for more tea and shortbread.
Back Cover
Summary
So, what do ya think? Do you like the design? Do you think there are better champions to fit the various Arcanas? Would like to hear some feedback and improve on the design, layout or so.
Special Mention
Check out CombatCube's version right here, it's cleaner than mine (well, because it's directly from champion screens, heheh): http://imgur.com/a/cjbYV