If you must gamble your Obols in Diablo 4, this is the best way of doing it
At some point, all Diablo 4 players realise that they're carrying more Obols than they know what to do with, and one way of spending them is to gamble.
The Purveyor of Curiosities is a rarely-visited vendor in Diablo 4, mainly because a lot of what they sell won't matter to most players for several hours into the game. The Purveyor only accepts a single currency: Obols, which is awarded from the chests that pop up after event completions.
Most of your early visits to the The Purveyor will be to buy Whispering Keys, which unlock Silent Chests you may come across in your travels in the open world.
Later on, however, you're going to find yourself under-equipped for certain challenges, especially if you land into a new region without upgrading your gear/get level-appropriate drops. This is where Obol gambling comes in. Using that same currency, you can roll the dice and pick any piece of gear or weapon on offer and see what drops.
Most of the time, you're going to get trash, but I've occasionally received the odd Legendary or two. Which is exactly why Obol gambling takes on a more crucial role the deeper into the game you get. See, Legendary (and higher) drops come with Aspects - unique modifiers that you can extract to use on other pieces of gear.
If you're deep in Diablo 4's endgame, you're probably missing a few Aspects that you continue to be on the hunt for, or perfect rolls of ones you already have. That's when Obol gambling becomes a source of drops, especially since you can target specific gear pieces/weapons.
The trick, of course, is to find out which Aspects drop on which gear slot, and how likely you are to get them from one vs the others. This where the Obol gambling tool comes in (via Icy Veins).
It is one of several useful tools on Diablo4life, a resource of build ideas, mechanic breakdowns, event tracker, World Boss timers, and much more. The gambling tool is quite simple to use. Just pick your class, Aspect type, and you'll see all Aspects that fit the the filter options - along with their drop odds.
If you know the Aspect you're looking for, you can enter its name outright. If you want some build ideas for Diablo 4, hit up the link. You'll also find many other useful guides in our main guide hub.