Yeah reapers chance * 20 for eth, rather than 10.
For gmb, it will be something like: [regular gmb drop chance] * [~10% superior (can look this up exactly on german drop calc)] * [1/3 + 2/3 * 1/2 enhanced dmg] * [1/11 15%ed] * [1/4 socketed] * [1/5 4os]
If that's right that's 1 in every 3300 GMB's.
Whoops forgot the skills. So that * 3 for 3 bow skills = 9900 GMB's
That number is already disgusting, let's make it worse!
Chance for white or grey item to be socketed on drop is 1 in 3 (sorry, that is actually making it better...) . Now if you socket one of those (non-superior) unsocketed white or grey items via a cube recipe the game gives the item min(x,rand(5)+1)) sockets where x is the maximum amount of sockets that item can get (depending on item type and ilvl). The item generation tutorial is not clear on whether the same mechanism is used on drop but if it is the chance for 5os on a sup GMB would be 1 in 6, not 1 in 5. (I asked fruit just now, will edit that in)
The Chance for a +3 Bowskill automod is 1 in 6. (+1 has weight 3, +2 has weight 2, +3 has weight 1)
The item generation tutorial is not very clear on superior drops but the order for items to be generated in is:
Unique - Set - Rare - Magic - Superior - Normal - Inferior
If the same principles apply that determine the first 4 chances then the chance for superior depends on qlvl of the item and mlvl of the monster that dropped it. It also indirectly depends on your MF because higher MF makes it less likely for the first four quality checks to fail. Good luck getting exact numbers here
I did a similar thought experiment for eth 5os 15ED sup BAs in 1.10+ once. It makes you want to stop playing the game
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The only thing that could make this better (and explain
@Bewitch 's GMB to some extent) is that some of the regular Archer type monsters in the game have a special TC assigned to them which is more likely to drop bows. Again the game just calls this thing bow followed by some number (like the other TCs) and it supposedly only contains Bows. If it contains Amazon bows then these Archers would be the best source of GMBs in the game.
A lot of the early act monsters have TC assigned to them by their type. Archers get 'Missile', Melees get 'H2H', Casters (like vampires or those lightning dogs) get 'Cast' and Ghosts get 'Wraith' (the one with the high chance for runes). For a lot of the act 5 monsters (including the 'guest monsters') they just dropped that whole system and copy and pasted 'H2H' for most of them
(I only know this because in the item generation tutorial/Hrus' MF guide there is a small aside on why it is not a good idea to hunt those archers specifically to get a WF. The reasoning used there doesn't apply here because GMBs are not in weap87, they're only in weap78 and the bow TCs are generated just like the weap and armo TCs, by grouping bows of a certain qlvl range together into a TC.)
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