Warren

Warren was an NPC located on the Bazaar Alley. Warren used to sell Stocks of Stonks for each; however, this was discontinued after only an hour after the 0.7.7 update.

Trivia
Warren isn't buying stocks yet!
 * Warren was the only NPC that had their item selling ability removed;
 * Warren was meant to buy Stocks of Stonks, as his GUI suggests, however, this feature was never implemented:


 * According to Changelog/2020/May 19, Warren is going on vacation for a long long time.

That means there is a possibility of Warren getting re-added in the future, or could mean that it is never intended for him to be added again, depending on how you look at it.