Furious Rooster is a 5 Star, Algebraic Rare Nice Lands creature in Card Wars. It can be obtained through as a loot in the Fionna & Cake Adventure.
Strategy
Overview
This is technically a stronger Dog Boy. While 5 magic points seems quite a lot to spend, it's definitely worth placing down the Furious Rooster, as it can be a great sweeper. Its Floop is something that even Dr. Death can't quite match up to, it can absorb a good deal of damage (as only 2 regular creatures can kill it by themselves without Flooping: Sandy and Dr. Death), and its attack is quite high for a Nice Lands Creature (Though Sgt. Mushroom and Fluffantry have a higher attack).
Counter
Mentioned above, use Sandy or Dr. Death (or a Sgt. Mushroom, considering you flooped it) to finish it off quickly before it starts wreaking havoc.
Crafting
This card cannot be crafted, and cannot be used to craft any card.