Good game, but would be better if you could start a chain from a number. Some people (like me) tend to start puzzles from the end and work our way backwards. It's easy to lose your place in a sea of ones when working without color.
@knottylovergirl and others who are complaining: the challenge took me maybe 10 minutes after not playing the game for over a month. And also, the GAME is "5 minute." Nowhere does the badge say "5 minute." Do you really deserve a medium badge for what was a rather easy and quick game before the challenge level?
I got frustrated with level 19 so I opened up the in-game link for the walkthrough, only to find the person making the video struggle and eventually give up, passing over the apple. SMH.
Burrito Bison was always one of my favorite games on Kongregate, but like many people here, the extremely tedious grind and the "Hey, give us ad revenue (when it works) to make the game more fun!" attitude totally ruins it for me.
I just had a bug at Team level 6 or so where I hit my geek, and then he just kept going and going. He'd go into the sky, smash down, then hit a ton of enemies on his way up, and then he kept on repeating that without my interference until the game froze when I got my second skill point in the last map.
You can upgrade after winning the game. Just click one of the maps after finishing the King's Castle.
Also, it seems impossible to get all achievements if you don't get 5/5 stars in the tutorial. Maybe allow players to replay the tutorial?