I would overlay a timer since most of your challenges have a time limit. Also it's pretty obvious that your were trying to mess up which isn't that funny. If you want to make sure you'll mess up easily and naturally then do the challenge, but with a surprise twist that makes it extra challenging. Good job with the lob mics, they help the audio a ton. Also good thumbnail.
There is great promise in these videos! Right off the bat the thumbnail is pretty good. In terms of improving the video I would try to add a little more editing perhaps with a small segment before each record explaining what the record is with a bit of music or something. Overall keep going!
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