I think it’s rather original.

Plus, the cumbersome cartoony falling anvils had me laughing — even though they are a real pain to get through, especially if you generated a troublesome platform in the way (at head level) as I did by mistake.

I don’t know how much is preprogrammed Unity and how much is on your part, but I like how the physics makes the cube able to get back on his feet after some nice wobbling. ;)

Remarks / Suggestions:

• Some sounds would give more life to your game. You can find and use free assets quite easily (sfxr and Freesound are just two examples).
• You can get blocked (! pun not intended); I think allowing the player to get rid of some platforms in some way (number limit, key to press…) would be handy.
• The checkpoints can be a little far when you have to build a long ‘bridge’, as you do to cross the lava.
• Too bad I read the punchline on this page before seeing it! Still, I like when the creator puts humour in his work.
• Of course, the game is super short. It sounds like a concept mixed with a joke; you might want to think about whether you could work something bigger up from it.
• On a side note, I like that you obeyed the constraint, as some do not. (I could not say if beginners are more prone to this behaviour?)

Good job having your first game here! :) You may have a sense of detail (seeing the font, the background mountains…) to put to use.

(I cannot give you any rate as my submission has not yet been taken into account, but I am proceeding mainly from the contributions with the lowest share of the votes; I will come back if I am given the opportunity. Even though the comments are more important than the mark. ;))