Leviathan the Yougling is 1 of 2 bosses. Levithan is known to be the harder of the two, because of the debuff he applies to you during combat. Levithan starts with 8500 health, 1600 armour, weapon speed of 2, and an attack range of 12.
Levithan can be found on top river, near the protoss side, and protoss top 1st tier tower. When Levithan is killed, he gives the team that killed him 400 minerals, and a buff that increases weapon and spell damage by 20%.
Levithan has two attacks, in one, he uses his tentacle like arm to attck you, in another he spews a green venom at you which decreases the damage you deal to him, because of this factor, it is much easier to kill Levithan when two or more people are engaging.