Because the champion stats on mobafire have not counted stacks or things like Archangel's Staff's 3% mana to AP, and Rabadon's Deathcap's 30% AP, I will make my own stats:

LEVEL 1(With Starting Items):

Health: 498
Health Per 1: 1.04
Mana: 522
Mana Per 1: 2.858
Armor: 15
Magic Resistance: 30
Ability Power: 14
Magic Penetration: 10%, 8.55
Movement: 300


Health = 420 + 78(Runes) = 498

Health Per 1 = 1.04

Mana = 310 + 200(Sapphire) + 12(Masteries) = 522

Mana Per 1 = 1.52 + 0.6(Masteries) + 0.738(Runes) = 2.858

Armor = 14.5

Magic Resistance = 30

Ability Power = 5(Masteries) + 9(Runes) = 14

Magic Penetration = 10%(Masteries) and 8.55(Runes)

Movement = 300 + 1.5(0.5% * 300)(Masteries) = 302



LEVEL 18(Fully Stacked Items):

Health: 2318
Health Per 1: 2.91
Mana: 3902
Mana Per 1: 9.898
Armor: 132.5
Magic Resistance: 60
Ability Power: 810
Magic Penetration: 10%, 8.55
Movement: 419


Health = 1610 + 630(ROA) + 78(Runes) = 2318

Health Per 1 = 2.91

Mana = 1211 + 1400(Archangel's Staff) + 725(ROA) + 350(Lich) + 216(Masteries) = 3902

Mana Per 1 = 3.56 + 0.6(Masteries) + 0.738(Runes) + 5(Archangel's) = 9.898

Armor = 82.5 + 50(Hourglass) = 132.5

Magic resistance = 30 + 30(Lich) = 60

Ability Power = 80(ROA) + 80(Lich) + 100(Hourglass) + 45(Archangel's) + 117(3% * 3902)(Archangel's) + 140(Deathcap) + 9(Runes) + 22(Masteries) = 593, 593 + 178(30% * 593)(Deathcap) = 771, 771 + 39(5% * 771)(Masteries) = 810

Magic Penetration: 10%(Masteries), 8.55(Runes)

Movement = 390 + 27(7% * 390)(Lich) = 417, 417 + 2(0.5% * 417)(Masteries) = 419

ALWAYS use frostbite (E) when enemies are chilled (by Q or R)

Practice landing the stun from your Q ability by pressing Q again while ice ball is flying and preferably be able to do a double hit (after the ice ball passes through an enemy - dealing damage, explode it right after to stun and do damage again)

Always go into the jungle while running away, your wall at skill lvl 5 can block a whole jungle path for 5 seconds, they'll lose you by then.

While laning mid, stand still and auto attack minions, don't actively move around. Fool your opponent into thinking you're not a good player. Then when hes not paying attention unleash your stun and frostbite combo, this could get you first blood :)

Pretend being weak and let your enemy attack you a few times, but make sure to bring his health low too, then when he chases you stun him at your turret.

Pretend being weak after doing damage to the enemy (make sure u bring him low on health) and bait your enemy into chasing you and trying to finish you off, some players don't know you're passive and will try every thing to kill you, even sacrificing them selves. But to their surprise you turn into an egg and he is in the middle of your minions, and you get a kill without dying. (note: only works in lower levels < lvl 25)

Use the long range advantage of flash frost (Q) and Glacial Storm (R) to tower dive enemies.

Control a team fight on the other side of a wall (inside the jungle), you can do this since your Q,E,R all do not require a target and can be casted through walls.

Always get blue buff and ask team mates for help, once you have this don't ever hesitate to farm minions with your ultimate.

Place Glacial Storm (R) at an enemy and immediately after place ice wall (W) behind him. For him to run away he will need to walk around the wall while slowed tons by glacial storm (R)

When ganking top or bot, hide in the brush beside the river and lead the enemies with stun followed by glacial storm slow.

One combo's burst is often not enough to bring enemies down, if they are close to their tower and are quickly running to safety, don't feel pressured to get the kill. Let them recall because you get time to farm and out level every one. When you are 3 levels above others you're guaranteed getting a kill next time.