After Tenku killed all the Rock Golems and Cactus Golems, he turned his target to the strongest monsters in the place, the Mithril Golems. Luckily, the area was divided into three by the metal wall. So Tenku only had to face two of the sixth-level monsters. He would be overwhelmed or might lose if he had to fight six Mithril Golems at once without using his full strength.
Even though the Mithril Golem can't regenerate like the Rock Golem, its defense is much more solid and might be the strongest of the monsters that Tenku has been fighting against. Moreover, the monster's attacks were dangerous from the information he got from the database in the Holy Union.
Tenku decided to try fighting one of the Mithril Golems with his bare hands first. He felt cutting or destroying that monster would be difficult even if he used his Phantasmal Object.