Three easy chess puzzles

Have you ever created a chess puzzle? Heaven knows we spend enough time solving them, it must be easy to invent one, right? Well, it turns out it isn't, at least not at first. I wrote these three puzzles from scratch, starting with a tactical idea that I wanted to build around. In each case, I ended up with a pretty different position than what I expected.

I've verified that each one is correct with a computer, so you won't be wasting your time if you try to solve them. As you would in a game, don't necessarily look for mate in every position, just play the best move you see.

There's something about the first two that feels very fake, but the last one seems plausible enough. Let me know what you think!

Puzzle one -- black to move: