Very nice job! You made a very fun game with a clear and engaging core gameplay loop. I especially like how the lasso starts to disappear if you start making it too long - it adds a twist as you start chasing your own tail and try to find a way to cut it off. I'd really like to see this concept be expanded on through additional enemy types, powerups, etc.
Just as a point of optimization, I never really felt the need to NOT be lassoing, so I think it might be beneficial to try out a version where you're always creating a trail? It'd be one less button to push and would allow the game to be easily played with just one hand