The Slaadi are a race of toad-like extraplanar beings from the world of Dungeons & Dragons. Natives of Limbo, they are the counterparts to the Modrons in that they serve as the living exemplars of Chaotic Neutral. Having originated in 1st edition as submissions of D&D fan Charles Stross to the Fiend Factory in White Dwarf, this meant that, in practice, they were portrayed as "Whee! Lolrandumb! I's funny!"
Slaadi are mostly remembered for coming in multiple different colors and their horrific breeding cycle. See, the basic Slaad come in Blue and Red colors. Blue Slaadi have a corruptive bite that physically and mentally mutates a victim into a Red Slaad. And Red Slaadi can implant eggs with their claw attacks that hatch into brain-eating tadpoles that subsequently turn into Blue Slaadi. The other colors are mutations on this basic cycle.
Slaadi are ruled by the Slaad Lords, who represent unique aspects of Chaos.
- Ssendam, Lord of the Insane, appears as either a giant golden slaad or an immense translucent-gold slime that resembles an amoeba with a human brain for a nucleus.
- Ygorl, Lord of Entropy, manifests as either a giant black slaad or a shadowy, sickle-wielding, bat-winged humanoid skeleton. Also played by the epic Michael Clarke Duncan in the game "Demon Stone"
- Tales of the Outer Plane added the forgotten Slaad Lord Wartle, whilst Dragon Magazine #221 added Chourst, Lord of Randomness, and Renbuu, Lord of Colors, who later became official in the Planescape expansion Planes of Chaos.
They got a lot of attention in 4th edition, but were really revamped; amongst other things, they changed from being chaotically random to wanting to dissolve all of reality into an endless chaos, changing them to the 4e definition of Chaotic Evil. They even got their own Demon Prince; Urae-Naas, a "female" slaad so bloated with eggs she can't walk anymore and has to drag herself along on her long arms and enormous tongue, who rules over the Phage Breeding Grounds; a bounded 10 mile demiplane made from the ever-rotting guts of her dead boyfriend, the Primordial Ramenos, which serves as the 53rd layer of the Abyss. The plane's most distinguishing feature are the legions of humanoid slaves trapped within the rotting walls of the entrail-caverns, screaming vainly for release before she drags her bulk their way and decides to implant them with her brain-eating progeny.
That's not to say they were entirely stripped of their randomness; they got a really fun "Slaad Reaction Table" in the Secrets of the Plane Below splatbook, where trying to talk to a slaad could result in it suddenly becoming convinced the party doesn't exist, bursting into croaking laughter, attacking them in a mad frenzy, or its head exploding violently before the rest of it nonchalantly wanders off.
Pathfinder replaced them with the more snake-like Proteans of the Maelstrom, creation and destruction in one, and who created much of the rest of the multiverse in their experiments with chaos. Whether or not this was a bad is a question long debated by philosophers (except the Abyss, most people are pretty sure on that one and it's generally considered the Protean's oldest mistake), but Proteans are open to debate on the matter. They're also open to dissolving you into raw chaos with warp waves, some of their castes are as violent as any Slaad, but on the whole they tend to be more philosophical than their froggy cousins.
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