Zazan the Unkillable is a time-limited global original unit. He's a bruiser that can hit quite hard, has high evasion, and some skills to help him survive. He can be a speedy assassin, or a decent evade tank if used with his Paladin sub-job to get Taunting Blade. His main downside is the mediocre range and lack of good area attacks aside from Taunting Blade or Leaping Slash.
His unique trait is his ability to survive attacks through his self revive skill (Fake Death) and Immortal Spirit. Stats-wise, he boasts one of the highest base ATK, AGI, and LUCK compared to most units, and has some pretty significant penetration towards Earth (TMR), Slash (master ability), and DEF (passive + Triple Split).
His main job skills have pretty good multipliers, but all of them are single-target attacks, and their range is not the best. Leaping Slash from main job sub-job can be a pretty good mobility move that can deal damage in an area, but taking that as the sub job means missing out on going with Paladin to get Taunting Blade and Immortal Spirit.