Tarko is the vicious Tarantula and the Main Antagonist of Tak-Zac Bug World. He is the original leader of the Tarantula Tribe until he was overthrown by Zoster and remained hidden in his own far away cave until he heard about Zoster's defeat. He then reclaimed his throne and continued ruling the Tarantula's. He is also the one who started the Bug Wars, as his goal was to kill off all the Ants and many insects in the Bug World.
Back in his youth, Tarko lived in a village where Tarantulas and Ants lived together where Tarantulas were weak and bullied by all the ants. Tarko, who is also a victim to the harassing, decides to get revenge on all the ants by training all the tarantulas to be stronger. Once they are fully trained, Tarko and the tarantulas attacked the village, destroying huts and sending the remaining ants fleeing in terror. With many huts and several ants destroyed by their rampage, the Tarantulas crown Tarko as their leader and named the village "Tarantutata". One day, a scientist named Zoster arrives in Tarantutata to recruit the Tarantulas to aid his revenge on Prof Antstein and all the other Bug Scientists for shunning him. The tribe refuses this offer until Zoster gave them his technology that improved their sanctuary. Tarko was quickly dethroned and was banished to the outskirts of Tarantutata.
Two years after the end of Zoster, Tarko finds his way in Tarantutata and reclaims his thrown from the deceased scientist. He explains to his tribe that during his banished life, he recruited outlaw cockroaches to help him prepare weapons and construction to bring back the Bug Wars again. He is also getting help from the three Roach leaders; Bossroach, Psyroach and Tankroach as his top henchman. However, Tak, Zac and their buds have arrived to the scene to thwart Tarko's plot, scotching the 3 Roach leaders in the process. Later on, Tak confronts Tarko to put an end to the Bug Wars for good. The two battle and Tak wins the fight by knocking Tarko off the tree. Tarko survives the fall but meets his end when he gets mauled and eaten alive by a caimen that attacked Tak and Zac earlier, putting an end to the Tarantula King for good.