Bite-Sized Update:
Replace some enemies with powerful Randbosses. Enemies of a Unique rank or higher, who are given random class talents.
Every rank of enemies has their own tier of loot.
As you level up, you'll see more of these buggers walking around.

You spawn at level 12, and can level up to a maximum of 200.

Increase your rank as you slay your foes.

You can see your kill counts and your rank experience in the quest log.

Many in Maj'Eyal have heard of "demons", sadistic creatures who appear seemingly from nowhere, leaving a trail of suffering and destruction whereever they go. Their Fearscape floats far above the skies, watching and waiting, but not idly; their agents scout the land, their legions build up their forces, and their scholars develop new spells and strategies. As the barrier between our worlds begins to crack under their scrutiny, helpless Eyalites have begun to disappear, whisked up to serve as their slaves and playthings. They imbue these victims with magical powers to better survive the ensuing stresses - can you use your new-found abilities to escape the legions of Mal'Rok?

Features:

• Start with a new class, the Doombringer! These avatars of demonic destruction charge into battle with massive two-handed weapons, cutting swaths of firey devastation through hordes of opponents. Armed with flame magic and demonic strength, they delight in fighting against overwhelming odds, softening up the crowd with waves of fire, then feeding on the flames and suffering of their surroundings to stay alive while quickly reducing any group to a pile of ash and gore.
• Unlock a new class, the Demonologist, with an all-new item enhancement mechanic! Bearing a shield and the magic of the Spellblaze itself, these melee-fighting casters can grow demonic seeds from their fallen enemies. Imbue these seeds onto your items to gain a wide array of new talents and passive benefits, and summon the demons within them to fight on your side! Ever looked at a gigantic demon-cursed minotaur and wished it was on your side for once? Well, now you CAN summon one to pound your foes into paste while you cast devastating spells from afar, or call forth a squad of Fire Imps to pelt your enemies to death while they exhaust themselves on your impenetrable defenses! Demons have persistent health, making them a little more precious than disposable necromancer skeletons or summoner beasts, but can be revived from death nonetheless.
• Two new zones, with all-new art, foes, and bosses! You've seen the plains of the Fearscape before, now see the lairs and headquarters of the demons themselves!
• Over 10,000 words of written lore to find! The demons were once an enlightened, peaceful race, hailing from a distant planet known as Mal'Rok; learn what drove them to plot Eyal's eternal torture! Discover monuments to each of the demonic species and noteworthy individuals, showing the place of honor each has among them! Get a glimpse into the culture and daily lives of these sadistic invaders and their brainwashed thralls!
• Unlock a new race, Doomelves: Shalore who've taken to the demonic alterations especially well, corrupting their typical abilities into a darker form. Blink away to safety, transform into a shadowy dúathedlen to hide in the shadows or prey on your foes with blasts of darkness, use your new resilience to soak up status effects and critical hits, and assault your enemies' minds to leave them unsteady in combat!
• Between the aforementioned classes and Doomelves, a whopping 75 new talents!
• Unlock two new cosmetic options! You know you've always wanted demon-horns.
• Two new events, appearing anywhere in Eyal!
• 20 new artifacts, with unique and interesting effects. Collect the Obsidian Treasures to amass more and more power! Slip your hands into the Will of Ul'Gruth and watch your sweeping blows smash down walls! Wear a giant hideous hell-mouth as a fashionable belt!
• 7 new achievements! Conquer the worst Urh'Rok's forces can throw at you, and hang their metaphorical skulls from your profile page!

Version 3.0: Compatible with ToME 1.5.0

This addon supports game play for character levels higher than 50, primarily for the infinite dungeon (I.D.). This implements a number of subtle changes, rescaling game mechanics and balance for character levels above 50 in the Maj'Eyal, Infinite, and Arena campaigns for ToME. The intent is to make it possible (though certainly not easy) to reach level 500 of the Infinite Dungeon. This is not a nerf or a buff to game difficulty per se, but, rather, an extension of the well-balanced game play from the Maj'Eyal campaign to higher levels.

Some talents and status effects have been adjusted to accommodate the higher character levels possible. You can see a summary of these by checking the "Infinite500" tab in Game Options.

Once a character enters the I.D., the level 50 cap is removed and normal stats-per-level progression is enabled from level 51 onward. The limit on how high primary stats may be trained is removed (limited by character level as normal) and dependent computed value limits are also appropriately increased. No additional Prodigies are gained automatically after level 50. (Note that additional category points and (rarely) Prodigies can be gained by completing I.D. challenges.) Talent mastery levels can be improved more than once, and talent levels are unlearnable as normal in the I.D.

NPC levels in the I.D. have been adjusted to be compatible with higher game difficulty settings.

Most monsters and bosses from the Maj'Eyal campaign are imported into the I.D. along with their respective unique drops.

Traps have been added back to the I.D.

Isolated shops can appear randomly in the I.D. There is guaranteed to be at least one shop on level 1, and they become more common for the first few levels, and then more rare with depth.

Random escorts may be randomly generated on each level in the I.D. unless a challenge has been started, until the normal number (9) have been attempted.

The lichform quest is completed in the I.D. with a new random drop instead of automatically being completed at the appropriate step. There is a new greater vault in the I.D. that affects this quest.

The Corruption/Hexes tree can be learned from a new random drop.

Most major events from the Maj'Eyal campaign are enabled in the I.D., and there is a new event that can award the cursed-aura tree.

Undead characters starting in the I.D. begin with an artefact cloak. This is similar to the Cloak of Deception, but its stats scale with character level and it can spawn randomly for other characters.

This addon incorporates some modified game mechanics:
The ability to shrug off critical hits has been changed. Instead of using the percent value to ignore crits completely, it reduces the crit multiplier by the same amount to a minimum of 100%.

Modified checkHit and checkHitOld functions are employed that allow for wider level differences between opponents (see http://forums.te4.org/viewtopic.php?f=36&t=35229).
Saving throws have been modified slightly to make them more effective at reducing the duration of status effects you fail to save against. (See http://forums.te4.org/viewtopic.php?f=36&t=36715 for details.)

Things planned for the future: scaling of world artefacts with character level, map effects with dungeon level.

CORE CODE CHANGES
Key code changes appear in:

Engine:
engine\generator\map\Static.lua
engine\interface\ActorStats.lua
engine\interface\ActorTalents.lua

TOME Module:
mod\load.lua
mod\resolvers.lua
mod\class\Actor.lua
mod\class\Game.lua
mod\class\GameState.lua
mod\class\Object.lua
mod\class\Player.lua
mod\class\interface\Combat.lua
mod\class\interface\TooltipsData.lua
mod\dialogs\LevelupDialog.lua
data\birth\worlds.lua
data\general\events\damp-cave.lua
data\general\events\drake-cave.lua
data\general\events\fearscape-portal.lua
data\general\events\naga-portal.lua
data\general\events\old-battle-field.lua
data\general\events\rat-lich.lua
data\general\objects\world-artifacts.lua
data\general\objects\world-artifacts-far-east.lua
data\damage_types.lua
data\quests\lichform.lua
data\rooms\greater_vault.lua
data\zones\infinite-dungeon\events.lua
data\zones\infinite-dungeon\npcs.lua
data\zones\infinite-dungeon\objects.lua
data\zones\infinite-dungeon\zone.lua
data\zones\ruined-dungeon\grids.lua

Other addons that affect these files might not be compatible.