INTRO
In Riot's eyes, Diana should be a diver and these changes are trying to push her even more in that direction. She's really the only one in that role who you can play in the mid lane (all other lack AOE) and I wish she'd stay there even after these changes.
Stat changes aren't considered here.
IMPORTANT: If you want to compare these changes to the live values here's a link to the wiki containing all the data you need: http://leagueoflegends.wikia.com/wiki/Diana.
ABILITIES
P - MOONSILVER BLADE
CLEAVE: After casting an ability Diana's next 3 auto-attacks in the next 3 seconds deal damage equal to 100% of her total AD to all units in front of her.
MOONLIGHT: Units affected by Diana's abilities are afflicted by Moonlight for 3 seconds, granting sight of them for the duration and 40 / 60 / 80% bonus attack speed against them. Additionally, every 3rd auto-attack on a Moonlight affected unit deals 20 - 250 (based on level) (+ 80% AP) bonus magic damage.
Notes
Possibility of including procing on-hit effects to her cleave autos. Don't know how would this come out balance wise. Her jungle clear might bee too good if she procs machete bonus damage on everyone cleaved. Lifesteal is also debatable.
The Moonlight part of her passive is basically a modernization of the old one.
Q - CRESCENT STRIKE
TARGET RANGE: 900
COST: 60 MANA
COOLDOWN: 10 / 9 / 8 / 7 / 6
ACTIVE: Diana unleashes a bolt of lunar energy that travels in an arc dealing magic damage to enemies hit.
MAGIC DAMAGE: 60 / 100 / 140 / 180 / 220 (+ 80% AP)
Notes
Her Q, Crescent strike, is one of her iconic abilities and it's mostly untouched.
Base damage and AP scaling a bit up.
W - PALE CASCADE
EFFECT RADIUS: 200
COST: 60 / 70 / 80 / 90 / 100 MANA
COOLDOWN: 10
ACTIVE: Diana shields herself for up to 5 seconds and creates five spheres that orbit her for the duration, detonating upon contact with an enemy and applying a slow for 1 second which reapplyies with every orb.
SLOW: 30% + 5% for every extra orb hitting them.
SHIELD STRENGTH: 40 / 55 / 70 / 85 / 100 (+ 4 / 5.5 / 7 / 8.5 / 10% Diana's maximum health)
If all five spheres detonate, Pale Cascade's shield is reapplied, stacking with its original shield, and its duration is refreshed.
TOTAL SHIELD STRENGTH: 80 / 110 / 140 / 170 / 200 (+ 8 / 11 / 14 / 17 / 20% Diana's maximum health)
Notes
The ability gets the Ashe W treatment - more smaller orbs which allow better detection.
Pale Cascade lost all of it's damage because it made Diana do too much burst and her damage is now more loaded onto her auto-attacks.
It also now slows, giving her some CC on a basic ability which is quite necessary for a diver. She will still have very little CC compared to others and no hard CC in her basic abilities.
Adding a max HP scaling instead of AP scaling encourages her to building tankier.
E - LUNAR RUSH
TARGET RANGE: 600
COST: 70 MANA
COOLDOWN: 12 / 11.5 / 11 / 10.5 / 10
ACTIVE: Diana dashes in a line, dealing magic damage to everyone she passes trough.
Hitting an unit affected by Moonlight gives you an option to cast another E after 1.5 seconds.
Units can be damaged only by one E, but proc Moonlight on both instances.
The ability goes on it's normal cooldown after the second E is used.
MAGIC DAMAGE: 80 / 120 / 160 / 200 / 240 (+ 40% AP)
Notes
Similar to Kled W in how it works.
Complete reset on Diana's old Ultimate and double the damage was a big problem because it gave her with her old W, too much burst. Again, a lot more of her damage should be in her auto-attacks now, so the damage of E is also adjusted.
The first E is now also a skillshot giving her some safety in lane and the option to do some crazy escapes.
Possibility of making her second E recast option start at 3 seconds and scale down to 1.5 with champion level (for comparison Kat E cooldown reduction is 3 seconds at level 1). She might be too oppressive in lane if she can retreat after 1.5 seconds, but that might not be the case because she really wants to proc her passive in trades and for her to do that she needs 2-3 seconds anyways.
R - MOONFALL
TARGET RANGE: 550
EFFECT RADIUS: 300 / 550
COST: 100 MANA
COOLDOWN: 120 / 100 / 80
ACTIVE: Diana starts channeling for 1.5 seconds while she retains her ability to move and attack (same as Ryze R channel). Her model starts to emit bright light warning units around her. After the channel ends, she has 1.5 seconds to reactivate the ability.
Reactivating the ability makes Diana blink up too 550 units away as she stays in the air for a brief moment (think Gnar R delay) and then slams her sword into the ground.
All units in an 550 area of the impact zone are pulled up to 275 units towards Diana while being briefly slowed for 80% just before Diana starts channeling again for 1.5 seconds.
A small zone also appears around the impact zone (300 units) in which all enemy units are silenced and the silence zone lasts for the next 3 seconds.
After Diana finishes channeling a beam appears from the sky and deals damage in a 550 units area around the impact zone in a span of 1.5 seconds.
MAGIC DAMAGE: 11.7 / 16.7 / 21.7 (+ 0.67% per 33 AP) of target's maximum health every 0.5 seconds
MAXIMUM MAGIC DAMAGE: 35 / 50 / 65% (+ 2% per 100 AP) of target's maximum health over 1.5 seconds
Both channels can be interrupted by CC.
Interrupting the first channel or not reactivating the ability by yourself puts the ability on half the cooldown.
Interrupting the second channel decreases damage. For every half a second of interrupted channel you'll lose one third of damage but the damage will still be applied in 1.5 seconds.
IMPORTANT: Hard to decide on the size of the areas because it's hard to imagine how big these are and I can't really test it myself in game. These are all numbers based on other champions which I found on the wiki and tried to compare the size with pictures. There were many variations of the ability and the ability can still definitely be improved.
Notes
Her new Ultimate is basically her old E on steroids. It gives her huge team fighting presence and great synergy with some champions for that juicy wombo-combo.
The maximum HP damage is used so there's no discrimination and everyone loses one to two thirds of their HP.
The silence is there to reward her if she pulls units very close to her. They won't be able to flash or to break her channel IMMEDIATELY (exceptions: Garen or Udyr who used their Q or E before they we're silenced).
The reason to put the first channel (similar to Ryze R) along with the second one is because I really wanted to make her blink in that first part and not dash. Blinking really makes it look powerful, but it doesn't really give that much counterplay to enemies. That's why there's a warning in the beginning as well.
The ability is quite powerful, but enemies get a couple of warnings before they get melted and there's even a way to stop some of the damage. Both Diana and her enemies should be wary of this ability - enemies on how to avoid it and Diana on how to land a perfect Ult.