Custom.WP-MSL-MAG is a Skell weapon mod Augment in Xenoblade Chronicles X. It increases the number of shots that missile-based weapons fire at the cost of reducing their damage. It cannot be crafted at the AM Terminal, and can only be found as a built-in augment on missile-based Skell weapons. It can be upgraded.
Diskbomb Oddities[]
Custom.WP-MSL-MAG has a strange effect on Diskbomb weapons. Instead of applying its effect to the total number of missiles, the effect applies to each individual missile. That is, with a rank I Custom.WP-MSL-MAG augment, instead of the Diskbomb firing a volley of three missiles, it fires six missiles over three volleys in a single auto attack. With a high-rank Custom.WP-MSL-MAG augment in place, a Diskbomb can fire an amount of missiles that rivals a battleship just in one auto attack.
This ability has even stranger effects if two Diskbombs, one with Custom.WP-MSL-MAG and one without, are equipped. If the augmented Diskbomb is in the left sidearm slot, the Diskbomb in the right sidearm slot will inherit the increased missile amount without getting reduced damage of having the Custom.WP-MSL-MAG trait. But if the augmented Diskbomb is equipped in the right sidearm slot, then the augment's benefit will not apply to either of the Diskbombs and the augmented Diskbombs held in the right Sidearm slot will deal reduced damage. Therefore it is optimal when setting up for Diskbombs to just equip 1 Diskbomb with this trait in the left and 1 Diskbomb in the right without this trait for the highest possible damage.