>> Use superpower RELENTLESS FRICTION to make fire.
>> Set fire to the grass surrounding the tower.

You don't recall having such a SUPERPOWER, but you begin to spin one of your WOODEN STAKES regardless.

YOWCH YOU GOT A SPLINTER. That hurts! Forget this FIRE idea; it's too dangerous!

>> Push the button again.

You go back below ground and attempt to push the BIG RED BUTTON again.

Unfortunately, the RED BUTTON is still ACTIVATED--it's depressed into the WALL and is unable to be pushed. You assume that once whatever is going on finishes, the BUTTON will pop back out.

>> try fitting through the gaps in the gate since they were silly enough to forget horizontal bars.

No dice! The BARS are still too close together for you to squeeze through. Despite what the "spin around your PICKAXE" action earlier may have suggested, you're not flat, and won't be able to get past the METAL BARS.

You go back above ground.

>> Bark like a dog.

This solves absolutely nothing, and you feel quite silly for doing it.

>> WRANGLE YOU UP SOME CATFISHES!!!!
>> ENGAGE CATFISH!!

...Oh yeah! The CATFISH! You'd almost completely forgotten about them.

You lean over the MOAT and peer down into the WATER in the hopes of seeing one of these elusive CATFISH. How can they be so scary that they can guard the CASTLE? As far as you can recall, CATFISH are just big, weird-looking FISH.

HOLY SNAP THAT'S A PIRANHA! You fall over backwards as two PIRANHA leap out of the MOAT and try to eat your FACE. Luckily, they're unsuccessful, but man that was a close call. The MOAT is teeming with tons of these PIRANHA! They can eat a COW in seconds, right? ...Or was that just a myth? Either way, you really, really don't want to find out!

How on earth could the VILLAGERS confuse a PIRANHA with a CATFISH? Perhaps they've never seen a real CATFISH and have no basis for comparison, but what could have made them attribute these things to a CAT--

Oh, wait.

PURR-AN-HA.

Oh man! You have to add this to your RIDDLES.TXT file someday.

Q: What do you call a laughing catfish?
A: A purr-an-ha!

(Okay, maybe it could use some sprucing up before you try it on anyone, but yeah, this is definitely comedic gold right here.)