The Revenge of Monster Magnet!

Besides the question if Monster Magnet works on bosses, there's also the factor of aggro.

A boss will always face into the direction of the player that does most damage for a set period of time. If the warrior uses MM all the time, he may suck a monster towards him, but the boss will turn always to the attacker who does most damage. So it's not gonna work. Rellik's 1/1+Poison attack has about 500 range, while ranged attackers only have 350 range, so ranged attackers are just not usefull with attacking him, because they get stunned all the time. You just need melee attackers like warriors, shadowers and buccaneers to kill Rellik effectively. They just have to stand "on" the boss to not get stunned at all. It's quite easy to attack him that way...

These scenario's (Pink Bean/Rellik) is just Nexon saying, pure damage isn't everything... Ranged attackers have to realize they just cant survive or be usefull at all bosses...

Assuming the TS isn't completely BSing this and it actually worked, then no, it seems like the boss would stay facing away long enough.

Also, NLs and Corsairs have 400 range (350 with Rapid Fire), and archers have 440 range.