Is my world starting to be corrupted?

Earlier today I noticed that my game had little squares that seemed uncoloured, but now there’s a wall missing and if I go underground black tiles surround me. Help?

I built a monument to Remeber me and my Freinds terraria nights

5 years ago today me and my freinds started doing Terri a Fridays however now none of us talk to each other anymore, the mannequin nes was each persons players lok

Was just about to finish the twins fight for the 1st time but solar eclipse said no

Greenhouse in the hallow. How'd we do?

what is y'alls most killed mob?

Jungle House

new terraria achievment idea: Pincushion

I made a church on my mage world

I'm probably gonna have guide be the priest

My trophy room

Night 1 of hardmode, spoiler, I didn't survive

This was the first night in hardmode for my ranger playthrough

Just a wee sketch