Hey!
This patch introduces the first instanced modes in the form of PVP.
Not everyone likes PVP but a lot of groundwork has now been setup for the future (like ET and map channels, leaderboards).
Also touched on balance changes, more to come. (no damage changes yet)

PVP Systems
Skirmish Mode (existing free for all sandpit)
PVP NPC, shows how many people are in Skirmish mode
New Arena map by @Polliwagon
Arena 2v2 Mode (new arena map with instancing)
Arena 3v3 Mode (new arena map with instancing)
Arena modes give rewards for each match, more for wins
MMR calculation and leaderboard
A lot of bug fixes in PVP

Inside PVP:
All damage is reduced by 75%
All healing is reduced by 50%
Revive skill is set to Lv.1 (priest skill and pressing F on dead players)
All summon stat inheritance is halved

Fixes and Improvements
Added autoattack hotkey (default C), which lets you press/hold to autoattack the highlighted enemy
Autoattack now starts after using a physical targeted attack skill
Pet loot interval reduced: 2s > 1s
Gear swap is now prevented for 3s after dealing or taking a hit
Increased see through wall radius in most maps
Added more information to stat tooltips
Shinobi Fan of Knives now lands where your cursor is, works like Stomp

Balance Changes
Gunslinger
Range changes affect the base weapon type and skills
Pistol/Shotgun range: 5 > 6
Gatling/Launcher range: 8 > 9
Rifle range: 10 > 12
Shotgun bonus range: 5 > 6
Flash bang backslide: 8 > 10 (same as Shadow Feint)
Flash bang charges: 1 > 2
Jump shot range: 10 > 15 (same as Earth Splitter)

Status Effect Immunities
Cards and Gear only grant 50% resist, instead of 100%
Priest skills still grant 100% resist
Attributes now grant 2/3% resist per point to designated status effects
Silence durations have been reduced, amongst a few other skill status durations, mainly affects Summoner, Priest and Wizard
You can now cast Cure/Mass Cure while silenced
Gunk Shot and Wide Poison no longer slows
SQ Execute replaced by Gunk Shot again

Designated Status Resistances by Attribute
Str: Bleed/Stagger
Agi: Slow/Freeze
Vit: Stun/Decay
Int: Silence/Burn
Dex: Poison/Blind
Luk: Curse/Weaken

For example Sunflora Card (50%) + 75 Int (50%) = Immune to Silence

Crit Def and making LUK a bit more useful
Crit Def has been reintroduced into the game.
What is Crit Def? Basically it reduces your Crit Chance
Monsters and players gain Crit Def per 5 Luk.

Luk Stat:
Currently adds
Crit per 3 Luk
Crit Damage per 10 Luk
Now also adds
ATK per 5 Luk
Perfect Dodge per 10 Luk
Crit Def per 5 Luk