The bulging taxbag is an unobtainable item added to the game alongside the The Fremennik Isles quest. Like the other tax bag items, it was likely intended to be used in the part of the quest where players collect taxes for King Gjuki Sorvott IV, but in the final version of the quest, players can only collect 29,000 coins, which results in a Hefty tax bag.
Unlike the obtainable tax bag items, it is spelt "taxbag" and has a "check taxes" left click option instead of "check tax".
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