The most recent patch of RIOT looked like a true revolution, finally the heroes of old got some attention which they desperately needed. I am sure everyone will have had a chance to see if these big tweaks actually made these champions viable again or if they just iddn't live up to the hype. On top of all the good news the new hero Zyra was added.

Now Zyra is already seen as pretty overpowered, the range on her casts is so long that's virtually impossible to get close to her before getting snared to the ground or shot at by her plants. You could compare her to Lulu when she was just added, you can basically play her anywhere and be really annoying while doing loads of damage with a lot of utility in teamfights. Nerfs will be coming for sure. More info on her abilities and such can be found Here

The rework on Xin Zhao was the most succesful of all 4 i feel like. he's been doing fine in toplane and as a jungler and i'm sure we'll see him back in action soon in competitive play. Malzahar, Twitch and Evelynn all needed some decent buffs, for The former these were not really game changing. The middle was reworked more towards an AD Carry and it might take some time untill people actually try it out for real. The latter her buffs were fine but it's been confirmed that she's going to be buffed again in the next patch, probably making her truly viable after being the number 1 troll pick for a long while.

all the info about the bug fixes, buffs and nerfs can be found in these patch notes:

* New Skins in the Store

- Mythic Cassiopeia

* PvP.net v1.63

- Improved initial seeding for Ranked Teams composed of skilled Ranked Solo/Duo players

- Summoner Profiles now display the highest Ranked Team rating, instead of Arranged Team ratings

New matchmaking upgrades

- Players who are under Level 30 are far less likely to face Level 30s
- Greatly improved matchmaking for premade groups of 4
- Matchmaking improved for highly skilled players trying to queue with lower skilled friends
- Matchmaking in Ranked Solo/Duo Queue now restricts the number of duo queue pairings on each team to 1 per team

* League of Legends v1.0.0.143

Zyra,Rise of the Thorns

Deadly Bloom
Zyra grows a bud at target location. After a brief delay it explodes, launching damaging thorns at all nearby enemies. If cast on a seed, Deadly Bloom grows a Thorn Spitter plant, which fires at enemies from afar.

Rampant Growth
Zyra plants a seed, granting vision of an area for up to 30 seconds. Other spells cast on seeds will turn them into plants who fight for Zyra.

Stranglethorns
Zyra sends forth vines through the ground to ensnare her target, dealing damage and rooting enemies they come across. If cast on a seed, Grasping Roots grows a Vine Lasher, whose short range attacks reduce enemy Movement Speed.

Whirling Death (Ultimate)
Zyra summons a twisted thicket at her target location, dealing damage to enemies as it expands and knocking them airborne as it contracts. Plants in the area are enraged, increasing their Attack Speed.

Queen Of Thorns (Passive)
Upon dying, Zyra transforms into a vengeful plant that fires one last shot before expiring.

Zyra, "can't touch this" can be viewed here:

* League of Legends v1.0.0.143 (continuance)

Akali

- Fixed: Mark of the Assassin's tooltip now states the correct Energy return amount

Amumu

- Fixed: Despair now displays a range indicator when hovered over

Corki

- Fixed: Valkyrie's targeting indicator now scales with distance from Corki

Evelynn (Remade)

Hate Spike

- 19/23/27/31/35 Mana, 1.5 second Cooldown
- Evelynn fires a line of spikes through a nearby enemy, dealing 40/60/80/100/120 (+0.45 Ability Power) (+0.4 bonus Attack Damage) magic damage to all enemies in its path
- Hate Spike prioritizes what Evelynn has attacked recently

Dark Frenzy

- No Cost, 20 second Cooldown
- Passive: Evelynn's spell hits on enemy Champions grant her 4/8/12/16/20 Movement Speed for 3 seconds (effect stacks up to 4 times)
- Active: Evelynn removes all slows affecting her and gains 30/40/50/60/70% Movement Speed for 3 seconds
- Champion kills and assists refresh Dark Frenzy's cooldown

Ravage

- 50/55/60/65/70 Mana, 9 second Cooldown
- Evelynn slashes a target enemy 2 times, dealing 35/60/85/110/135 (+0.5 Ability Power) (+0.4 bonus Attack Damage) magic damage with each strike
- Evelynn then gains 60/75/90/105/120% Attack Speed for 3 seconds

Agony's Embrace (ultimate)

- 100 Mana, 150/120/90 second Cooldown
- Evelynn impales all enemies in the targeted area, dealing 15/20/25% (+1% per 50 Ability Power) of their maximum Health in magic damage and slowing their Movement Speed by 30/50/70% for 2 seconds
- Evelynn siphons their pain, gaining a 150/225/300 health shield for each enemy Champion hit which lasts up to 6 seconds

Shadow Walk (passive)

- Evelynn fades away into the shadows. She can only be seen by nearby enemy Champions or true sight
- While in stealth, Evelynn regenerates 1% of her max Mana every second
- Casting spells, taking damage, or dealing damage unstealths Evelynn for 8 seconds

The mistress of Stealth, Evelynn can be watched in action here:

* League of Legends v1.0.0.143 (continuance)

Gangplank

Parrrley
- Now refunds half the mana cost if Parrrley kills the target

Garen

Perseverance
- Added a buff timer to show when Perseverance will reactivate

Gragas

- Fixed: Body Slam no longer stops when encountering created terrain (ex: Anivia's Crystallize)

Graves

Smokescreen
- Sight reduction range reduced to 675 from 800

Jax

- Fixed: Counter Strike's dodge component now works properly against Shen

Kassadin

Riftwalk
- Damage reduced to 60/70/80 from 60/90/120
- Ability Power ratio increased to 0.8 from 0.5

Malphite

Ground Slam
- Armor ratio reduced to 30% from 50%
- Now has a 0.2 Ability Power ratio
- Attack Speed reduction duration reduced to 3 seconds from 4

Malzahar

Call of the void

-Delay is now consistent at 0.6 seconds
- Now deals damage in a single hit - rather than two separate hits
- Now grants vision along the entire line path - rather than only at the two end points
- Now deals damage to units surrounding the end points

Null zone

- Cast time removed - Malzahar may now cast this ability while moving
- Damage now starts 0.25 seconds after casting the ability

Nether Grasp (Ultimate)

- Malzahar ignores orders that would cancel his ultimate within the first 0.5 seconds of Nether Grasp
- Voidlings prioritize champions immobilized in Nether Grasp above all other priorities

Summon Voidling (passive)

- Voidlings prioritize enemies Malzahar is autoattacking if Malefic visions isn't present
- Voidling pathing and general AI improved
- Voidlings will now hide in brush and won't attack if Malzahar is in brush and not in combat
- Voidling dance animation added

Mordekaiser

- Fixed: Children of the Grave's initial damage now correctly draws turret aggro

Morgana

Black Shield
- Cooldown increased at earlier ranks to 23/21/19/17/15 seconds from 15 at all ranks
- Cast range increased to 750 from 600

Soul Shackles
- Leash range is now more accurate (now updates every 0.25 seconds from 0.5 seconds)

Nocturne

Shroud Of Darkness
- Shield duration reduced to 1.5 seconds from 2

Paranoia
- Cooldown increased at earlier ranks to 180/140/100 seconds from 160/130/100
- Updated Umbra Blades tooltip

Nunu

- Fixed: Visionary will now grant free cost spells even if spells were ranked up while the Visionary buff was already active

Orianna

General
- Fixed: Attack Range is now 525 at all times.

Command: Attack
- Ability Power ratio increased to 0.5 from 0.4

Command: Shockwave
- Fixed: Now stuns enemies that were in the middle of a movement skill.

Sejuani

- Fixed: Arctic Assault no longer stops when encountering created terrain (ex: Anivia's Crystallize)

Sona

General
- Basic attack and Power Chord missile speeds increased to 2000 from 1500
- Aura persistence duration reduced to 1 second after deactivation from 2
- Global cooldown reduced to 0.5 seconds from 2

Power Chord
- Power Chord now resets your attack timer so you can use it immediately

Crescendo
- Now deals all its damage instantly, rather than over time
- Fixed: Opponents can no longer Cleanse the damage portion of Crescendo

Shen

Ki strike
- Damage reduced to 4 + 4 per level from 4 + 6 per level

Teemo

Camouflage (passive)
- Fixed: Teemo now gains the Attack Speed buff instantly after leaving invisibility

Tristana

Explosive shot
- Fixed: Passive damage no longer activates from spell damage
- Fixed:Fixed: Tooltip now reflects the Ability Power ratio

Twitch (Remade)

Stats
- Attack Range increased to 550 from 500
- Base Health increased to 389 from 356
- Health per level increased to 81 from 78
- Base Mana increased to 220 from 180
- Mana per level increased to 40 from 35
- Base Attack Damage reduced to 47 from 51.56
- Attack Damage per level reduced to 3 from 3.3
- Attack animation improved

Ambush
- 60 Mana, 16 second Cooldown
- After 1.25 seconds, Twitch becomes invisible for 4/5/6/7/8 seconds and gains 20% Movement Speed. Twitch gains 30/40/50/60/70% Attack Speed for 5 seconds after revealing himself

Venom Cask
- 50 Mana, 13/12/11/10/9 second Cooldown
- Twitch hurls a cask full of venom to target area that slows targets by 25/30/35/40/45% for 3 seconds and adds 2 stacks of Deadly Venom

Expunge
- 70/75/80/85/90 Mana, 12/11/10/9/8 second Cooldown
- Deals 20/35/50/65/80 plus 15/20/25/30/35 (+0.2 Ability Power) (+0.25 bonus Attack Damage) per stack of Deadly Venom as physical damage to all nearby enemies affected by Deadly Venom
- No longer removes Deadly Venom stacks

Spray and pray (ultimate)
- 100/125/150 Mana, 120/110/100 second Cooldown
- Twitch's basic attacks become powerful piercing bolts with 300 bonus range, and Twitch gains 20/28/36 Attack Damage. Each bolt deals 20% less damage to subsequent targets down to a minimum of 40% damage. Lasts 7 seconds.

Deadly Venom (passive)
- Damage reduced to 12/24/36/48 per stack from 15/30/45/60

A guide of the new and remade Twitch can be viewed in this video:

* League of Legends v1.0.0.143 (continuance)

Urgot

Acid Hunter
- Damage adjusted to 50/80/110/140/170 (+1.2 bonus Attack Damage) from 10/40/70/100/130 (+0.85 total Attack Damage)
- Lock-on missile cast range reduced to 1200 from 1500
- Fixed: Rank 1 range is no longer higher than the other ranks

Noxian Corrosive Charge
- Cooldown increased to 15/14/13/12/11 seconds from 11 at all ranks
- Cast range reduced to 900 from 950

Hyper-Kinetic Position Reverser
- Cast range reduced to 550/700/850 from 700/775/850

Vladimir

Sanguine Pool
- Movement Speed bonus now decays over time

Xerath

Arcane Barrage
- Reduced the delay between casting the spell and the impact to 0.5 seconds from 0.875 seconds

- The visual indicator for the ultimate will appear at the start of the cast bar instead of at the end

Xin Zhao (Remade)

Stats
- Base Attack Speed increased to 0.672 from 0.658
- Attack Speed per level increased to 2.7% from 2.5%

Three Talon Strikes
- Now reduces his other ability cooldowns by 1 second with each strike
- Attack Damage ratio increased to 1.2 from 1.0
- Cooldown reduced to 9/8/7/6/5 seconds from 10

Battle Cry
- Passive: Heals Xin Zhao for 26/32/38/44/50 (+0.7 Ability Power) every third basic attack
- Active no longer reduces other abilities' cooldowns
- Cooldown reduced to 16/15/14/13/12 seconds from 24/22/20/18/16
- Mana Cost increased to 40 from 35

Audacious Charge
- Now challenges the target
- Damage increased to 70/115/160/205/250 (+0.6 Ability Power) from 70/110/150/190/230 (+0.4 Ability Power)
- Slow increased to 25/30/35/40/45% from 20/25/30/35/40%
- Slow duration increased to 2 seconds from 1.5
- Range reduced to 600 from 650
- Cooldown reduced to 13/12/11/10/9 seconds from 16/15/14/13/12

Crescent Sweep (ultimate)
- Now knocks all unchallenged targets back
- Now has a 1.0 bonus Attack Damage ratio
- Cooldown increased to 100/90/80 seconds from 75
- Armor and Magic Resist bonus adjusted to 15/20/25 per champion hit from 25 + 7/10/13 per champion hit
- Now has a new particle

Challenge (passive)
- Xin Zhao challenges his target with his basic attacks and Audacious Charge, reducing their Armor by 15% for 3 seconds. Only one target can be challenged at a time.

Yorick
- Fixed: Unholy Covenant (Passive) no longer reduces true damage

Ziggs

Satchel Charge
- Cooldown reduced at earlier ranks to 26/24/22/20/18 seconds from 30/27/24/21/18

* Summoners Rift
- Outer turret vision range increased to 1095 from 800

* Twisted Treeline
- The Dragon on Twisted Treeline now has the same chat kill announcement as the Dragon on Summoner's Rift

* Items

General
- Avarice Blade, Heart of Gold, Kage's Lucky Pick, and Philospher's Stone now have counters in their tooltip to indicate how much gold the item has generated over the course of the game

Heart of Gold
- Health reduced to 200 from 250

Ionic Spark
- Added a counter to show when Ionic Spark will be charged

Philosopher's Stone
- Health Regen per 5 seconds reduced to 15 from 18

* Co-Op vs AI
- Changed the way bots evaluate towers to better take into account minions and enemies
- Changed return to base logic for bots to make them more likely to heal and purchase items
- Dominion bots should now properly ignore invisible units when deciding to defend capture points
- Beginner bots are now less likely to assist each other during kill and retreat situations
- Fixed: Bot assist logic now works during the laning phase
- Updated Ashe Bot's item build
- Master Yi Bot should now properly purchase Sanguine Blade on Dominion instead of The Bloodthirster

* General
- Added character portraits to the Spectator-mode Dragon and Baron kill announcements
- Fixed: Spectator no longer occasionally causes floating text announcements to be permanently displayed throughout the game
- Fixed: When using time controls, gold numbers will no longer get stuck on the screen for some users
- Fixed several issues that occur when reconnecting, including ghost minions, invisible champions, untargetable towers, and strange store behavior
- When disconnected, the game will now attempt to reconnect automatically

A video with some explanation about some of the changes can be seen here: