Krail's bad batch of battle droids

Krail's bad batch of battle droids was a batch of modified battle droids created by Doctor Krail of the Confederacy of Independent Systems, which would benefit greatly from the dangerous droid soldiers. Krail hoped Clone Force 99—the "Bad Batch" of clone troopers—would discover his experiments as the ultimate test for his droids. Dispatched to the moon of Hylanth in the Outer Rim Territories after reports of the modified droids reached the Galactic Republic, the clone Bad Batch, who were under orders to find and destroy the droids, encountered their robotic counterparts and fought for survival against them.

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