Board Thread:Plants vs. Zombies Wiki Discussion/@comment-4009269-20140213201430/@comment-5792287-20140724094326

It IS pay-to-win. Most pay-to-win games can be beaten without paying despite being called pay-to-win, but it's usually harder than beating The World's Hardest Game (or v2 of that) without dying.

Even with my skills, I doubt I could beat all of that horribly hard-looking Kung-Fu World without using Gems.