Just a quick video showing off how it's possible to beat the level 'Thar She Blows Up' without the Clawstring.
For anyone that cares about the specifics: when you reach the first wheel of bombs, bounce on top of them until you reach the top, then head through the boss door. After the cutscene ends the game auto-equips the Clawstring even if you skipped it. But if you pause the game, hit Retry and select the Boss Fight option, when the boss arena reloads the game will not give you the Clawstring like it usually would.
Without the Clawstring at your disposal you are at a disadvantage since you can't just grab the bombs from a distance; you have to get up close and grab them, which makes you more vulnerable to not just the Ruffled Ruffian's attacks, but also falling off the stage. Despite the added difficulty it is entirely possible to beat the level no strings attached, if you'll pardon the pun.
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