As you may know, today the Rare drop table (RDT) got updated. Jagex has provided us with the updated rates for the Rare Table as well as the official rates for most of the Super Rare Table's drops.
You can find them on https://runescape.wiki/w/Rare_drop_table.
Type /wiki rdt on the in-game chat for quick access.
External link →This might be dumb and I might misunderstand how the drop table works but if we know the chance to get every item on the super rare table except one item, wouldn't we know the chance for that item? It seems everything on the super rare table is based on x/640, couldn't we just add it all up? However doing so on the wiki with the number seems to imply that there is 0/640 for hsr table on the super rare. This would imply that hsr is on its own separate table and the chance to hit that table is chosen as some point prior to deciding what item you get from the super rare?
You're not dumb (and no-one is dumb for asking questions) - the chance for HSR is on top of what you win from the Super Rare table rather than replacing it. EDIT: Actually, I'm misremembering. If you succeed on rolling for a HSR, you'll only get the item from the roll (Cheese+Tom batta, Blurberry special or HSR) and not both the HSR roll item + Super Rare table drop.
Whenever you roll the Super Rare table, there's a separate roll for your attempt at the HSR. If you succeed, it then checks to see what tier of luck you have access to - if you don't have tier 4 luck then you roll a Cheese+Tom Batta. Then there's another roll and if you're successful then you get a HSR and if you aren't, you get a Blurberry Special.
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