ScourgeBringer

Greed is the friendly wizard NPS merchant that sells you health and weapon upgrades. He can be found in all realm. Simply buy all his merchandise In a single encounter with him ( no need to buy everything for the whole run, one encounter suffice to unlock this achievement. First world has the cheapest ones. Beat the boss then backtrack to buy everything from him because the boss give quite good amount of blood. ( due to RNG you may not be able to buy everything so simply restart ). The passive skill that you get at the chiming tree after you beat the game for the first time gives you a 500 blood start.


Spoiler**

When you activate root chaos and enter the realm 6. You can actually kill Greed. If you killed him before getting this achievement. Dont worry. It is not missable.
There are two friendly wizard selling you still. One is wearing the exact dress of greed and is named xipo... and the other one is wearing green robe named Lefanu. You got to buy everything from the green wizard Lefanu to unlock the achievement. If you press B and open the map , it is still says greed shop but lefanu will be the person selling

Greed is a merchant commonly found throughout the realms. He sells 3 items for blood droplets, a currency you accumulate by killing enemies. All you have to do is buy all 3 items in a single encounter-- the achievement is NOT to purchase every single item Greed could possibly sell.

Depending on your price luck, it could take several thousand blood to buy Greed out. If you're struggling, I recommend saving up until you've seen Greed a few times during a run. There is also a helpful skill called "starting package" that lets you begin a run with 500 blood.