GMS v134 - Monster Life & 8th Anniversary

What's the "rare item drop level" variable?
(asking for opinions since I doubt data explains it)

Here's every mob with it in GMS.

 Spoiler

Name	Rare Item Drop Level
Jr. Balrog in Another World	2
Advanced Pianus	2
Fabricated Griffey	2
Snow Yeti	2
Kenta's Seruf	2
Scholar Ghost	2
Crimson Balrog the Kidnapper	2
Fabricated Manon	2
Fabricated Mihile	2
Crimson Balrog	2
Jr. Balrog	2
Over Timer	2
Lilynouch	2
Advanced Griffey	2
Advanced Manon	2
Snowman	2
Master Hoblin	2
Joe Joe	2
Dyle	2
Galacto-Drill	2
Mano	2
Ergoth	2
Coco	2
Fabricated Pianus	2
Crimson Balrog of Competence	2
Mushmom	2
Stumpy	2
Rurumo	2
Little Dragon	2
Griffey Herald of Heroes	2
Peeking Lord Pirate	2
Enraged Lord Pirate	2
Shadow Cygnus	2
Snipe of Competence	2
Lilynouch of Competence	2
Fabricated Hawkeye	2
Nine-Tailed Fox	2
Toy Black Knight	2
Griffey	2
Faust	2
Angry Frankenroid	2
Eregos	2
Tae Roon	2
Pixiemom	2
Zombie Mushmom	2
Kentaurus King	2
Lord Skeleton	2
King Slime	2
Poison Golem	2
King Clang	2
Mano	2
Advanced Leviathan	2
Alishar	2
Dodo	2
Seruf	2
Super-Charged Poison Golem	2
Zeno Eclipse	2
Papulatus	2
Queen Pepe	2
Pianus	2
Corrupted Bastille	2
Leviathan	2
Fabricated Eckhart	2
Ika	2
Master Birk	2
Eliza	2
Jr. Balrog in Forgotten Shrine	2
Timer	2
Deo	2
Zeno	2
Fabricated Oz	2
Fabricated Irena	2
Angry Lord Pirate	2
King Centipede	2
Yokai Sage	2
King Sage Cat	2
Frankenroid	2
Hermonniny	2
Manon	2
Manon, Herald of Heroes	2
Snowman of Competence	2
Lyka	2
Master Harp	2
Orchid	2
Chaos Pink Bean	3
Separation Test	3
Little Dragon	3
Busted Ravana	3
Joe Joe	3
Chaos Zakum	3
Zakum	3
Pink Bean	3
Smart Manon	3
Ravana	3
Ika	3
Hilla	3
Horntail	3
Hilla (Gray Maiden)	3
Spiegelframe	3
Chaos Horntail	3
Cygnus	3
Ephenia	3
Magnus	3
Captain Darkgoo	3
For HP Link	3
Mystic Hilla	3
Pink Zakum	3
Mystic Horntail's Soul	3
Mystic Zakum	3