This is a stand-alone Quality of Life pack that improves some minor things about ToME gameplay.
This pack adds particles to certain effect types (such as "dizzy stars" for stuns and confusions, or green bubbles for poisons).
Background: It is otherwise difficult to tell if or when certain effects procced or not, and it is also kind of obnoxious having to check each and every enemy for whether they're affected by something or not.

Allows the player to pick multiple classes, turning all enemies into Randbosses as a counter-measure.

In order to activate this addon, look at your Game Options for a new tab.
EXP penalty you suffer from using this addon has been modified, from 0.5 to 0.85 (You only lose 15% EXP now)
Original Author is StarKeep, all credits go to him, I do not take credit for any of his work, I only modified the EXP penalty. - Rae
Updated Version 1.4.1:
- Possessor and Adventurer can now be chosen in the Multiclass menu

Tired of being alone on your adventures? Tired of being an archmage with no one to give that unique battleaxe to? Tired of having no one to use your healing spells on? Tire no more, for now you can create fully controllable additional party members to join you on your adventures, each as capable as your leader. Included is a sustainable talent to control each party member as their turn comes up to allow fully tactical combat when things get rough.

-Grants the ability to add any number of additional members to your party each with their own race and class, allowing you to take on higher difficulties.
-Select race and class of the party members to be created by raising and lowering free talent levels in a new automatically unlocked talent category and then activate the spawner talent to create a new member.
-Mark characters you no longer want to be deleted on death by selecting them and using that same talent on a character created by it.
-Revive dead party members by channeling a talent for 100 turns.
-Gain full control over each member whenever it becomes their turn by activating a sustainable talent on any of your party members.
-Gold is effectively shared between each party member allowing each character to use stores and trainers as well as benefit from gold based talents.
-Can create any race, class, and gender of which you have unlocked and is able to be played in the infinite dungeon, even from addons.
-Can define any party member's ally compassion by the game's default give orders dialog.
-Can define any party member's self preservation by the game's default give orders dialog.
-Can disable friendly fire damage via a sustainable talent on a per-character basis.

-!Due to how alchemists are designed, you will not be able to take direct control of their golems if the alchemist is not your main character, but should still function correctly elsewise.
-!To prevent compatibility issues with other addons, the talents this addon use to create new party members still require you to have a talent point to raise them, but will not cost one to raise.
-!This addon will not add its talents to a character that was created without the addon enabled.
-!Due to some potencial save-breaking issues, you will only be able to change zones with your main character selected.

For a list of changes, please see the change notes on steam or by reading the int.lua file included in each downloadable version.

A complete rework for Archer.

Adds a collection of my races.

Modifies the character creation dialog to bypass the lock check for races and classes, allowing characters to be created using locked races and classes. Doesn't actually unlock anything.

Frequently Asked Questions:

• Hey, the character creation dialog still says I have locked races/classes! What gives?
• Will this prevent me from unlocking things?
• The latest version of the game has a new locked race/class. Will I need a new version of this addon to access it?
• What the heck is this Runic Golem thing?

A combination of all my celestial addons; Firmamancer, Primal Chosen, Trench Strider, Radiant, the Empyreal fork, and the newly added Bloodtide Cultist.

One year has passed since the one the Orcs call the "Scourge from the West" came and single-handedly crushed the Orc Prides of Grushnak, Vor, Gorbat, and Rak'Shor.  The Allied Kingdoms, now linked by farportal to their distant, long-lost Sunwall allies, have helped them conquer most of Var'Eyal.  The few remnants of the ravaged Prides are caged...  but one Pride remains.  Kruk Pride, isolated on an island, is the last orcish settlement that stands; they, too, face their impending doom.  The Sunwall has blockaded the only exit point from the island, and now, the technologically advanced civilization of Steam Giants have come down from the mountains to take their homeland with machines and weaponry unlike anything else on Eyal.  Kruk Pride has reverse-engineered their technology before; their only hope is to do it again and rise up against the Pride's foes.
 

Features:

• Explore a whole new campaign from level 1 to 50, one year after the events of the original Tales of Maj'Eyal campaign. Liberate the Orcs (or die trying) by rising up against the Sunwall, the Steam Giants of Atmos, and other dangers that may lie in wait...
• Play as one of three new races: the battle-hardened Orcs, the brutal Yetis, and the unstoppable Whitehooves. Discover their stories, their pains, their hopes... and their awesome racial powers!
• Risk your life in over 20 unique zones! Explore the ruins of a lost city, lay siege to the Sunwall forces at the Gates of Morning, and raid the Steam Giants' mining quarry - each has its own unique foes and hazards, leading each to feel and play different from the others.
• Play as one of the four new tinker classes: Gunslingers, Sawbutchers, Psyshots and Annihilators! Plus a class evolution: Technomancers! Crush and rend your foes with heavy metal, electrocute and immolate them with your gadgets, charge across the battlefield or nimbly strafe in style - each plays differently, and none provide any shortage of ways to slay your foes.
• Master steam technology to build powerful tinkers to augment your equipment. Need to close in a bit quicker? Turn your boots into rocket boots! Having a hard time deciding whether to shoot someone or stab them? Build a Hand Cannon into your gloves, or deploy a Weapon Automaton to do the stabbing for you! If you have a problem, steamtech has a solution, usually involving explosions; with over 80 different powerful contraptions to craft, enjoy unparalleled versatility and trying something different with every playthrough.
• Master the tactical uses of over 140 talents! Fire bouncing trick-shots and psychic-infused shots, use your steamsaws as shields or wheels, terrify your foes with long mechanical arms - there are no "boring" talents here, everything has its own special applications and properties!
• Use advanced technology in the world of Eyal! Burrow through sand, plant bombs to destroy tunnels, and discover that you aren't alone in using it...
• Infusions and runes are for puny humans; implant new medical injectors to pump an array of experimental chemicals into your body! Injectors can use any (infinitely reusable) salve in your inventory as long as they're off their cooldown, giving you versatility you've wished you could get with a couple of inscriptions.
• Loot over 70 new and powerful artifacts. Pump lead into foes with big guns, quick guns, and explosive guns! Shred them with saws that maim, saws that thirst for blood, and saws that aren't really saws! Violate common sense by strapping a rocket to your back and calling it a jetpack!
• Enjoy dying in horrible and exotic ways at the hands (or claws, jaws, guns...) of over 140 new creatures! Not mere piles of stats and chain-stuns, these foes will provide unique challenges - suffer the Sunwall's newest cosmic spells, the new breeds of ritches that infest and multiply, the Steam Giants' elaborate defense systems, and find new strategies to adapt to each!
• Earn a trunkload of achievements! Have your accomplishments recognized for liberating the Orcish people, displaying exceptional mercy or cruelty, or showing your prowess with impressive feats! Give a boss a fate worse than death, show Sunwall forces how frustrating it is to fight a Radiant Horror as a paladin, come out on top against impossible odds, display a suicidal lack of situational awareness, and wear a badge of pride or shame for each!
• Read roughly 27,000 words of new lore to immerse yourself in the world! Learn how things have changed since the Scourge's campaign, feel hatred and/or pity for your foes, uncover grand schemes and sinister plots, and notice the elaborate connections between Var'Eyal's numerous factions. Every zone has a story behind it, and every story ties into a bigger picture; enjoy a tale of horror and humor, of intrigue and glory, of despair and hope.
• Earn the right to use the classic (and Ashes of Urh'Rok) classes in Embers of Rage, and the new tinker classes in Maj'Eyal! Play a Brawler in the East to fulfill your life-long dream of suplexing an entire nation of giants, or play a Sawbutcher in Maj'Eyal to shred through Dreadfell in a whirlwind of sawblades and steam!

Adds the Ruined, an afflicted subclass.

Ruined are spell casters that have been twisted by the curse.
Now they have become harbingers of destruction, ravaging countrysides with lightning storms and obliterating the minds of their foes.

Allows modification of gains for stats, resources, experience gain, category points, and prodigy points. If you would like to be able to modify other values post them in the comments.

UPDATE: I've added the ability to modify stat and level maximums. I have also added the ability to customize which levels stats, talents, talent types, and prodigies are gained at. This allows for alternative leveling schemes such as gaining 2 class points on every even level and 2 generic points every odd level. For example, the max/milestone level could be set to 100, xp gain at 300, and all intervals doubled with alternating offsets for a faster early game, a slower late game, and increased potential for early game specialization.

NOTE: All options are accessed after loading a character through the game options window under a new Levelup tab. They will only appear for characters created after the addon is enabled.

UPDATE: I've added the ability to toggle unlearning of prodigies and stats. I've also reworked some of the internals to improve compatibility with future changes.

This addon replaces ToME's floating combat text:
- Shows the damage type (lightning, etc.) as icons or text!
- Text moves in a consistent direction and should be much easier to read than ToME's default for a variety of reasons.
- Can group damage for an entire player turn, or by every action taken - choose how much information you want to see!
- Various font sizes to choose from
- Various font coloring options (color by major damage type, use the default red / green, etc.)
- Text duration can be changed to fit your play style.
Icon credit for this addon goes to Lorc.

(if you like this addon, be sure to also check out my Map UI improvement, Easy Map!)

Adds the Afflicted Class, Possessed.

Adds High Wights as a playable race: tough, psionic undead who arise naturally yet stand outside the natural order.

Also adds Forest Wights as a playable race: undead with a connection to fire, light, and nature.

Models by Rexorcorum.

Have you ever noticed that the newlines in ToME's battle log
don't always correspond to where you took your turn? This addon places
"--------" turn separator lines at the exact points you made a move so
that you can easily tell what has taken place since your last move, and
what text corresponds to the turn before that. Via addon config, you can
even replace ToME's newlines with these new separators, should you wish to
do so.

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!

Adds the White Monk, a warrior subclass.

The White Monk wields no arms, instead using intense focus and training to turn their body into a weapon. They fend off enemy blows with their immense willpower and can preform healing and regenerative rites. Primary stats are Dexterity and Willpower. White Monks have the unique ability to project unarmed melee attacks at a distance, with talents that allow them to strike many targets in a area, as well. White Monks have a base damage modifier for hand gear of 60% Dex and 60% Wil, and gain some of the same benefits to unarmed attacks as Brawlers.

Includes seven new talent trees and incorporates a few existing trees from Warrior and Rogue classes.

Rending - Attack your foes from afar and sap their energy.

Mending - Heal and cleanse yourself and even prepare a rite that can ward off death itself.

Fending (generic) - Ward off enemy assaults, directing some damage to your stamina pool.

Agile Combatant - Move across the battlefield with unmatched agility.

Martial Arts - Master the art of unarmed fighting and gain bonus strikes from your attacks.

Black Belt (locked) - Learn advanced fighting techniques to cripple your foes and react with finely honed reflexes.

Transcending(locked) - Directly manipulate your foes' spirits to sap their energy and learn to project your spirit to assail all nearby foes.

Follow one of the Six Ways with a set of class evolutions for the White Monk:

Way of the Rushing Bull

Way of the Flying Arrow

Way of the Open Palm

Way of the Arcane Flow

Way of the Transcendent Spirit

Way of the Hidden Viper

Full details in the forum thread.