fatal scream is used below 5% and has an extremely long windup, such that a full party will drop it before it finishes unless severely debuffed or underbuffed
it's evasion is obscene, if you don't have sushi and multiple acc buffs you're going to have trouble doing enough to hold hate.. without elegy, it's melee is going to be extremely painful on a single sam
if you have a decently geared group of 119s, sam brd cor whm should be sufficient.. whm should hug the mandy and brd stands out of aoe to finale photosynthesis and immediately curaga1 after each dream flower(if the brd is quick, sam can provoke as soon as awakened and it should never move)
with excellent gear you can drop the cor, but that's probably as low as you can go