This clear attempt was made with the intent of using items and/or units that most players were able to obtain or would have at the time of it's release. I realize players are less likely to have some items (Irurose, Keion) or units (Regulus, Number 2), but I hope this shows that top-tier units such as Ragsherum, Melia, Rem, and Kayas aren't absolutely necessary for this fight.