By upgraded skills I mean "if else" skills like this one:

Decrease ATK/DEF/MAG/SPR (55%) for 3 turns to one enemy

If used after Directive - Hacking System or Directive - System Update, name changes into Directive - Hacking System :
Decrease ATK/DEF/MAG/SPR (70%) for 3 turns to one enemy

This bug allows you to use the upgraded 70% break without using the version or CD first. It works on any units on both GL and JP.

Reproducing the bug

To reproduce this bug, you will need to enter 2 separate battles:

Battle 1

• You can use any battle, including the Room of Recollection or Training Dummy.
• The unit should use an upgraded skill as their last action. Any upgraded skill will do, even if it's completely unrelated to the one you want to cast next battle.
• Give up or win the battle.

Battle 2

• On turn 1, use multicast with that same unit. Any skills second cast and up will be upgraded without meeting their conditions.
• This will only work on turn 1, or rather the first turn that unit act. Pre-emptively auto-casting something will not break this bug.

Example: A.I. Katy

Training Dummy

Trial