New save system. Your save code will now be written to a text file in a tkok saves folder in you war3 folder. You can also save in the old way. The path is: x:\pathtowarcraft\TKoK_Save_Files\TKoK_3.1.3\ each version will have its own sub folder. The heroes are saved in this format: HeroType-ExpTotal-Goldtotal.txt to help prevent overwriting data. You will have to manually manage the different copies. This also helps makes backups.. just in case! When in doubt, just sort the folder by date for the latest copies. Inside the text file will be stored more info besides just your password.
New lightning system. The chain lightning spell is no longer used in the map. This is intended to fix some crashes (like at narith, muarki, and vj's air elemental) releated to the possibility of double DestroyLightning calls and wc3's special indexing of lightning.
Passwords for 3.1.3 will not be backwards compatible because of the talent system changes.
Warriors, C. Knights, and Rangers will get a free talent respec due to the edits to their trees.
All 3 Naga units within the Temple of Sanctity (beyond the Trails area) have been weathered by the heat of the desert (HP reduced by 15%)
Lady Myren multishot spell is now physical damage and reduced by armor. Increased base damage. This is a nerf.
The saved inventory items was increased to 15
The inventory is now 2 colors. The first 15 slots (saved ones) are gold like usual, the non saved slots are now gray
Crit text tags now move upward at 1/2 the speed of normal text tags
Added a new Target Mark system:
-m1 to mark your selected unit with a Red mark
-m2 to mark your selected units with a Blue mark
-mclear to clear all marks
Endurance now gives more block
The -1 level of xp penalty, for normal mode only, now applies to enemies level 27+ instead of 28+
Respec price formula changed. Now cheaper at lower levels. Also now available at Tol Calm Front Gate. This is intended to help newer players who mess up their stats.
+Gold items now effect gold earned from selling to vendors
Magic resist has a hard cap of 50%
Vials of Blood for both Barrens quests now have a unique model (easier to see them now)
Waypoints now require the proper quests to be completed to use them
Added a second elixir merchant at Grom'Gol so you can do all your shopping in one place.
Replaced hard/medium/easy difficulty text at hero selection with a new Tip that may be a little more helpful
Enrage and Curse of the Chaotic will no longer put you in combat, do less damage (.7 per level from 1 per level), and cannot be reduced by damage prevention

Threat System
The aggro bars now fill from empty (white) towards full (now orange). If you have aggro the bar will instead empty from red to black as someone catches up, instead of staying solid red.
The Threat Calc system has undergone a complete rehaul. Individual spells no longer have aggro bonuses (except taunts put you to 120% of leader: chaotic grasp and charge). Tanks now have a multiplier to damage and healing aggro of: (3 + (level * 0.05))
The aggro system changes will make it easier to off-tank. For example you now gain some aggro when enemies attack you. The increased ability to off-tank can be considered a buff to the barbarian and some other classes.
You now gain aggro for the following things:
Dealing damage gives aggro
Dots have a 30% aggro reduction for non-tanks
AoEs have a 50% aggro reduction for non-tanks
Crits have a 60% aggro reduction to the bonus damage from critting, for non-tanks
Heals give aggro in 675 aoe. It had a 25% reduction.
Dodging, blocking and being hit gives aggro

Generic Bug Fixes
Fixed item drops from Crueltis and Tal'Navi to properly always drop the loot they should (fixed items that had a chance not to drop as well)
Fixed an "Issued Order" command that could fire the incorrect trigger. (Most commonly seen with the Arcanists Blast spell triggering the -lastpass command)
Fixed an issue with -tt and spending talents outside of the Actions Menu
Implemented a new TerrainPathability system (by Rising_Dusk) to help with pathing for Knockbacks, Tossing, Grips, Pullins, Pounce, and the new Charge ability
Lord Naztar properly rewards exp/gold again
All "Pack" mobs now auto gen 1 threat on near by party members when first pulled if they have no threat on them at all
Fixed an issue with Narith's Frozen ability that can break the buff system and cause other issues down the road
Fixed an issue with Narith's Frozen ability that caused it to deal no damage
Many more talent / tooltip adjustments and fixes
Fixed some spellings of fierce and cutthroat, and the icon on a leather helm
Fixed elixir of spirit tooltip to match the numbers in code (no change to how good it is)
Mark of Replenishment, mana ward and ranger's Viper talent can restore fractional mana but only display a whole number in blue. Changed the displayed number to round to the closest number instead of rounding down.
Fixed an overflow recalc issue with the HeroAbility struct. Full recalcs could wipe out hero data from the wrong column causing the "1" damage or healing bug until your hero gets recalced.
Fixed what could possibly have caused the Vjaier Air Elemental random crash
Removed the threat system/bars from a bunch of units that did not need it (stationary objects to attack, portals, Centaur Ranger vipers, etc.)

Arcanist
Damage increase for arcanic blast

Barbarian
Damage increases for deep slice, blade storm and berserker rage spell damage
Cleave spell now correctly affected by armor

Chaotic Knight
Empowered Chaotic Grasp is now a 2 point talent for 35/70% (was 3 points 25/50/75)
Increased aoe range for mindblade
Added Chaotic Stance to the talent list: 1 point talent that adds bonus threat generation to the Knight and reduces all damage taken by 5%
Fixed chaotic grasp to do damage *after* putting you on top of the aggro list, not before
Changed chaotic attacks. mindblade no longer has a debuff. it now makes mind blade have a 50% stun chance on main target, and 20% on splash targets. it used to only be able to stun main target. if you roll stun on a boss, you get 20% dmg instead.

Druid
No talents are required for bear form tanking anymore. Just being in bear form adds bonus threat generation
Added Hero Glow to all forms
Pounce can now target allies for a quick easy escape. Targeting an ally will give both you and the target a Courage buff. The buff increases movement speed by 15% and reduces all damage taken by 10% for 8 seconds. The buff will vanish if the 2 linked units move further than 400 units apart.
Fixed bug where wolf and bear damage skills were not being reduced by enemy armor. Re-balanced some ability coefs to lessen the nerf.
Druid now has a special stat calculation formula for Attack Power while in Tree/Caster form as to not gimp Strength / Dexterity builds in this form. Bear and Wolf forms remain unchanged in the way Attack Power is calculated
Frenzy duration increased from 5s to 8s
Empowered Moonfire changed. Less splash damage, but now has a single target damage bonus. Also fixed bug with moonfire splash damage
Increased power gain from Enrage

Hydromancer
Damage increases for tsunami and ice nova single target
Buffed thick ice
Buffed purity of water (note: i just found out it doesn't multiply with talents like emp purify or emp tsunami, they both increase from the base value)

Paladin
Changed armor/dodge talent to scale less at higher levels
Changed paladin +dmg talent. better at low levels, about the same now, won't scale up as much in the future
Mark of Sanctuary AoE can now crit heal
Divine Touch with Light Infusion AoE can now crit heal
Imp Light Infusion now heals more with larger range

Phantom Stalker
Hail of Blades has a new animation
AoE Radius on Bladefurry increased from 300 (from 250)
Gash and Puncture cooldowns lowered from 4 to 3

Ranger
Nerfed sniper training and deadeye to normal values
Increased damage of multishot a little. Note: its damage is reduced by armor (so is hail's)
Deleted imp poison trap (it never worked, btw!). Moved the point to deadeye
Buffed imp frost trap damage
Buffed emp hail of arrows
Nerfed emp explosive arrows single target bonus from 15% to 12%

Shadowblade
Soul Drain no longer keeps ticking if the unit dies with the debuff still active
Imp Dark Blast now only increase a specific defbuffs duration 10 times. If the buff expires then is reapplied, the cap is reset.
Buffed time strike damage 10%
Nerfed unholy embrace heal amount
Adjusted unholy mastery and dark tap
Decreased dark blast buff duration additional increase per level

Warrior
Defensive Stance removed from the game (along with all its talents and mods)
Counter-Attack removed from the game (along with all its talents and mods)
Armored to the Teeth talent removed from the game
Ignore the Pain talent removed from the game
Charge! Added to the warrior's ability list. Allows the warrior to charge to the selected target causing a knockback (if it can be) and dealing line damage to all units in the path. Improved Effect will make Charge! also taunt the target (the way Chaotic Grasp does)
Intimidating Shout renamed to Intimidating Bellow
Heroic Shout Added to the warrior's ability list. Grants you 55% damage reduction for 3 seconds and will increase your threat on all near by enemies by based on your level. Imp talent gives 35% damage reduction to near by allies. Emp adds 2/3 of a second duration
Added Defensive Stance (passive) to the talent list: 1 point talent that adds bonus threat generation to the warrior and reduces all damage taken by 5%
Added Natural Resistance to the talent list: 2 point talent that adds magic resist to the warrior
Changed warrior mitigation talents to use flat values
New Battle Orders formula and no more bonus effect on yourself
Imp shield slam deals 20% bonus dmg on targets it can't stun
Increased damage for shield slam a little, and reduced damage for intimidating shout a little

Muarki
Lowered hp of his minions by 10-15%

Vjaier
Portal Spawned mobs now spawn with 1 threat on a random player in range of the fight
The exit X,Y loc for the Toss Out and generic forced exit was moved slightly more west to avoid walking back into the fight right before it resets and causing bugs

Crueltis
Crack the Sky (starfall) damage in phase3 reduce by 20%
Adjusted Shockwave, Hail of Arrows, Warrior's Cleave, and Crack the Ground (moving earthquakes) to properly be physical damage instead of spell

Tal'Navi
Shardling Minions melee damage reduced by 30%
During phase1 and phase3, the boulders now take 100% damage reduction from AoE classified spells (currently 75%)
Adjusted the damage types of the minion landing bolt, flying boulders, and boulder crush damage to properly be physical damage instead of spell.
Made a few adjustments to make the fight a little easier on legendary and HC mode
Lowered damage of rock throw 15% and made them slower