Contaminated Colosseum/Strategies

Strategy #1
5 Summoners L70+ make short work of this BCNM. Before beginning the attack, assume positions around Evil Oscar on the perimeter of the "arena" at the top of the hill. Each Summoner should then cast Garuda, use a Yagudo Drink, and then Assault the malboro. Keep using Predator Claws as often as possible. Should Garuda fall to melee damage or the Breath attack, immediately recast and re-Assault. Occasionally, a Summoner may be put to sleep, but none are likely to take any damage. With a healthy assault, the mob shouldn't move from the middle of the ring. This strategy also works with 3 summoners and 2 beastmasters. You use the same positioning as the summoner and using Courier Carrie is reccomended. The beastmaster pets provide cover should any of the Gaurdas fall to melee or breath damage.

Source

Strategy #2
Another Option is with only 4 jobs Summoner, Ninja x2, and Whitemage.


 * The Whitemages primary job is to Raise 3 in case Ninja #1 fails to kite correctly and heal when needed.
 * Start off by having the Summoner take out Garuda and hit Evil Oscer with Predator Claws. Let Garuda fight Oscer until she dies. The ninja must then Provoke.
 * The ninja should kite (sticking to the left wall going down the hill and returning upwards on the right wall) until he sees Oscars pre-Extremely Bad Breath message 2 times, Send out a warning that he is going to force the AOE Death move, and then run once the message that Oscar is reading the move appers. If the ninja does this correctly Oscar will be stuned for a few seconds. This gives the ninja time to turn around and head up the hill.
 * While Oscar is stunned from failing to use the Bad Breath attack this also gives the Summoner a chance to use Predator Claws again.
 * Just repeat those to steps having the Ninja use a Down and Up path on the entire hill, stopping to only let Oscar use his attack, and while stunned the summoner uses Predator Claws. If done correctly there shouldn't be any death and no need for the second ninja to act.