Use VPS to host servers not your own PC.
But in case you have to. just pick one that had good CPU & Memory & Storage (https://github.com/rathena/rathena/wiki/System-Requirements)
Some of them are hard-code on client, You can see Red Potion effects if you adjust script to another bonus it's still had red potion effects.
But there are options for you. See D:\rathena\doc\effect_list.txt
Try @ effect <effect number> you will see effects then use it to item script like specialeffect <effect number>;
Maybe time is missing.
@mute <time> <player name>
@mutearea <time>
@unmute <player name>
Mutes or unmutes a player (prevents talking, usage of skills, and commands).
@mutearea will mute every player on screen for the specified time.
If you don't care about Thai languages, Try follow my guide: https://www.youtube.com/watch?v=cDYt3LySTOc&list=PLQI8wpKGPj97RXXlI5PEvSAtwhKQfnwi3&index=14