The End of Evolution. Experiment Kraj was a mutant ooze constructed from a mass of highly-mutable cells, designed to adapt based on any other mutant created by the Simic combine. With this trait, the Simic planned to use experiment Kraj as the ultimate mutable creature.
Apex Predator Let Loose. Shortly after its creation, experiment Kraj’s activation was thrown off-plan when its creator, Momir Vig, was killed in an attack from his enemies. Without Vig’s careful control, Experiment Kraj was let loose on the city of Ravnica, unstoppably draining the Simic’s mutants for their powers, evolving into the deadliest creature Ravnica had ever seen.
Adapt to Survive. Experiment Kraj’s evolution was rapid and chaotic, draining mutations from other creatures, and instantaneously growing defenses against the latest damage it has suffered. Kraj could even gain access to the traits of non-Simic creatures by absorbing them into its cytoplasmic mass. This eventually caused the Kraj’s downfall – its absorption of the demon Rakdos proved to much for it, and killed it from within.
Experiment Kraj is an extremely powerful enemy, but only when it has, or has had access to other Simic creatures to drain their mutations. It can serve as a terrifying final boss for a campaign on Ravnica, where a Dungeon Master could have an ambitious Simic scientist try to repeat Momir Vig’s historic experiment, but make the same mistake…
You can find all my Ravnica content here!