This is a throwback to a fun game we played as kids - press a button and make your plastic hippo gobble up marbles in an arena as fast as you can! But we all know that's totally unrealistic. Hippos can't eat marbles! I'm pretty sure they appreciate cheerios though, and this one is happy to be your breakfast companion.
I printed about a thousand different versions of this before finding a set of colors I was happy with in the end - let me know what you think!