FE6's Ending Judgment in FE8 by C
This hack referenced @GratedShtick 's Killing with a specific item having story significance, sincerely praise him!
Usage
For Buildfile users, include "FE6EndingJudgment/Installer.event" in you Buildfile, then you can use it like this:
ASMC KillWithSpecialWeapon
CHECK_EVENTID 0x7b
BEQ 1 0xC 0
/* write the true ending */
LABEL 1
/* write the fake ending */
ENDA
For FEBuilderGBA users, you need to install "FE6EndingJudgment/Installer.event" at Advanced Editors - Insert EA, then you need to find KillWithSpecialWeapon’s function address in the sym.txt file generated at the same time, then you can write events like this:
Enjoy it 