Campaign Concept: Queen Ascending

The adventurers have spent the first few levels hunting down the lair of a necromancer. Nothing unsurprising; the general dark cowl and bones aesthetic one would come to expect from a communer with the dead. The necromancer has seemingly been practicing new forms of raising undead and releasing their experiments upon the local countryside.

Summoner by Piotr Dura

Through valiant fighting and careful investigation, the adventurers have found the dark tower of their nemesis. They've scaled the staircase, avoided traps, discovered the true extent of the wizard's machinations. They burst through the final door, entering the necromancer's observatory, from which they can use the moon's power to fuel their rituals.

The fight begins. Spells are launched, blades collide, spectres shift through the floorboards to defend their master.

Then the tower walls explode. An airship has arrived. Three figures swing across on ropes, landing in the tower. One incapacitates the necromancer and shifts out of view, appearing on the ship once more. The other two draw their weapons, ready to engage the players.

Your necromancer has been stolen by githyanki raiders.

An Alternative Slaad

Ideas presented here are partially adapted from Goblin Punch's slaad post, especially in terms of colour-hierarchy.

Slaadi are the multiverse's antibodies against a universe of pure order, and they look like frogs. Both of these points are equally important.

The true face of chaos.
(photo from Philadelphia Zoo website)

Slaadi are drawn to sources of chaos and unpredictability. They are enraged by stagnation, order, and law. A slaad would get as equally angry over an evenly trimmed lawn as it would over a fully lawful realm. When they find a source of frustration, they seek to change it. They do not destroy it: destruction can come as a result of this change, but the object or person in question must remain in some form post-slaad intervention.

Sometimes the simplest way to change something- or someone- into a more tolerable, unpredictable state is by making the creature of interest into another slaad. Like frogs, slaadi lay jelly-like eggs, which turn into tadpoles and metamorphose into adults. Like non-frogs, slaadi inject their eggs into hosts through their ovipositor-like claws.