Psion
"Psion" is the D&D way of saying "psychic". It is a common opinion that psions in D&D are overpowered. This stems from time and time again of game designers trying to make psychic powers something different than spellcasting, and fucking up the game design doing it.
It is believed that Dungeons & Dragons' psionics is cursed. That these books are not RPG supplements, but grimoires of a sadistic cult, playing with your emotions. To have any D&D psionics book present in the room will ensure you always roll poorly.
AD&D
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In 1st edition, psions were normal characters that rolled 99-100 on d100 during chargen, and gained extra spellcasting that didn't require spellbooks nor devotion to a faith. They had their own psionic-only battles that were invisible to non-psionics, and required their own combat matrix on the DM's screen so you could play rock-paper-scissors-lizard-spock with the five attacks and five defenses. Only one attack could actually affect non-psionics, and it was less effective than casing Feeblemind or just punching someone in the jaw. Everyone else would just stand around and watch an invisible, silent fight between people standing perfectly still. Whoop-de-doo.
Third edition
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D&D 3.0 had horrific mechanics: the ultimate M.A.D., where you needed a high stat for every subcategory of psionics to have a decent power. There were no supplements for 3.0 psionics, amd we're okay with this.
In 3.5e, psionics were simpler: Psions were accountant spellcasters who kept track of a mana pool. Psionic powers didn't level up (well, almost all), instead the psion would spend mana ("power points") to increase a power's effect. Other players raged about this being h4x because a psion could turn themselves into glass cannons and screw a BBEG if they really wanted to. Most of the complaints about psionics came from pro spellcasters, who want to be the only ones with an "I win" button.
3.5e psionics only had one good class: the Psion, or psychic sorcerer. Psychic Warrior was just a better fighter (which isn't saying much). The wilder was a psionic warlock, the Soulknife was a shitty knock-off of monk WITH LIGHTSABERS11!!ELEVEN11!!! just like that hot Asian chick in X-men comics. The other classes described in the Complete Psionic book aren't worth mentioning.
Fourth Edition
In 4e, psionics had their simplest rules ever. Psionic classes had the standard powers every class had (at-will, encounter, and daily), but their at-will powers were weaker. They had a mini-mana ("power points" again) to pump up at-will powers, and the mini-mana refreshed during a long rest just like encounter powers. There were four psionic classes in the tank/heals/dps routine: Ardents were your empaths and psychic healer leaders, Battleminds were your front-line Defenders with iron-hard skin and superspeed, Monks would wire-fu around the battlefield to be high damage Strikers, and Psions would be Controllers using Force-push, mass telepathy and conjuring.
Fifth Edition
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Dungeons & Dragons 4th Edition Classes | ||
---|---|---|
Player's Handbook 1 | Cleric • Fighter • Paladin • Ranger • Rogue • Warlock • Warlord • Wizard | |
Player's Handbook 2 | Avenger • Barbarian • Bard • Druid • Invoker • Shaman • Sorcerer • Warden | |
Player's Handbook 3 | Ardent • Battlemind • Monk • Psion • Runepriest • Seeker | |
Heroes of X | Blackguard* • Binder* • Cavalier* • Elementalist* • Hexblade* • Hunter* • Mage* • Knight* • Protector* • Scout* • Sentinel* • Skald* • Slayer* • Sha'ir* • Thief* • Vampire* • Warpriest* • Witch* | |
Settings Book | Artificer • Bladesinger* • Swordmage | |
Dragon Magazine | Assassin | |
Others | Paragon Path • Epic Destiny | |
*·: Non-AEDU variant classes |