After competing the Djinni's first two tasks, you will have but one more to finish before proceeding. This one is of course a bit of a doozy. You will have to seek out and destroy the Djinni's rival, Ezrek. The Djinni will open up a portal to Ezrek's lair, meaning that you don't have to fumble around on the overworld map looking for it. Head into the portal when you are ready.
When you arrive in Ezrek's lair, you will find yourself greeted by a hoard of Netherlings. These creatures aren't too tough, though. Simply use big area of effect attacks to destroy the Tentacle creatures when they pop up, and hit encroaching monsters with stun or slow attacks to slow their steady advance. Other than these few basic tricks, there really isn't much to making it to Ezrek. Simply follow the waypoint and beat your way through the weaker enemies.
As you begin the fight, pop several potions or let your health and mana regenerate if they need to. Although the enemies before him were simple, Ezrek himself is a brute of a boss and likely the toughest you've faced so far. Ezrek can shrink from huge to merely big on the magic circle on the platform. From here, he will summon minions to damage you and distract you from the real fight. You know the drill here. Eliminate the minions before getting back to the real fight. Of particular note are the shadow magic flinging projectile users, who you should most definitely kill off first. Their beams will slow you down if you can't get rid of them quickly. When the minions are done for, return to Ezrek and smash him up.
Once you have dealt a certain amount of damage, the boss will teleport away and leave you momentarily ondering if you have defeated him. Of course, you have not won the battle just yet. When Ezrek returns, he will summon two Mirror versions of himself. These clones have lower HP than the real deal, but are otherwise identical to the boss. Ignore the clones and try to keep your focus on the real enemy. As you chip away at his health, he will teleport around the arena in an attempt at confusing you and making you believe that one of the clones is in fact him. Don't fall for his tricks, and always keep a close eye on the Djinni. Hover your mouse over each enemy to figure out which is which if you get lost up in the fight.
Again, when you have dealt enough damage, Ezrek will jump away and commence a final attack. He will summon more Mirror copies of himself, this time accompanied by some more minions to boot. The boss will begin to teleport around the arena at great speed at this point. This section of the fight is more related to endurance than anything else. Keep drinking potions, kill off the smaller enemies and the projectile enemies, ignore the Mirror copies, and focus on the real deal. Once you have finished the boss, he will explode into a shower of loot. The Djinni will appear to reward you for your quest well done. Now that you've fulfilled all of his requests, head back to Zeryphesh to prepare for the end of Act 2.
