In Iris Online, the defender class can not be chosen at first until your Human knight character reached level 50. The advance human class considered to be as the ultimate tanker in the game. With their high defense buffs and stun skills, that makes them ideal in a party. Due to high Mana consumption, they need to stock more mana potions.

The following information is about the Human Defender skill(Iris Online Gold) build. Have a look.

Stat Build Tips
You need to have decent points in the Psyche to have larger mana pool since the Defender greatly depends on skill spells. Vitality takes most of the points to make your character(Iris Online Gold) have more defence and HP points.

PVE
Defender are essential to the party. With the high defense buffs and stun kills, they're ideal when it comes to boss hunting and mobbing. When it comes to solo play, it would be a bit cumbersome due to the character's low damage rate. It's best to be in a party since you'll kill the mobs faster.

PVP
Despite having low damage rate, the high defense buffs and the stun skills puts them at great advantage. You'll just have to use your skills wisely and know when to use them.