Prototype Tailed Beasts

Prototype Tailed Beasts (尾獣のプロトタイプ, bijū no purototaipu) is the titanic behemoths. They are differentiated by the number of tails they have, ranging from one to ten. The tailed beasts are living forms of chakra, sometimes referred to as "Chakra Monsters" (チャクラのバケモノ, Chakura no Bakemono), giving them immense reserves of especially strong chakra that far outmatches most shinobi. The tailed beasts' chakra is coloured red.