I came down to the print I started an hour earlier going completely haywire. Hotend was caked over. I had been having more stringing issues on the last two prints but since it's cave terrain I didn't really care. All in all I have done about 25-20 spools of mostly PETG.

Is this about normal for everyone else?

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What printer?  Does it have a PTFE lined heatbreak?  

If so, it looks like the PTFE liner might be breaking down.  Pull it out, and trim off the lower 10-15mm or so, and reassemble.  Make sure the trim is square, and butted firmly against the nozzle when you reinstall.

Alternatively, is it just loose?

My first Prusa had over 11,000 hours in it, which is about 550 spools of filament. I had the hitend fail once because if an electrical issue that led to a thermal runaway and the aluminum block basically turned to silly putty..

My second Prusa I sold at about 3,000 hours or so, which is about 150 spools. Was still on first hotend, zero issues.

Your nozzle needs to tighten against the heat break that's screwed into the heat break if it's a all metal hotend. Also tighten the nozzle when it's heated up to temperature.

If you don't you'll get oozing around the hotend like you see. You don't want the brass nozzle to tighten against the heat block.

Elegoo Neptune Plus.

Changed to a new hotend and back to normal.

It was running for about 36 hours prior to this print. The nozzle was pretty tight when I changed it out.

The nozzle is part of the hot end, but not _the_ hot end, not sure which one you really meant there, based on the pic.

Nozzles wear out. Many of the color additives in are abrasive to some extent.

Nozzles come loose from the heat/cool cycles.

The ends of the PTFE bowden tubes eventually degrade as well, as others have mentioned.

And when you change a nozzle, do it when the hotend is hot.

Hotends themselves don't wear out unless someone is really ham-handed changing nozzles, the fitting at the top, heater, or thermocouple. A lot. A spare is nice to have mainly because you can clean one while still printing with the other.

My mistake then. My NOZZLE shit the bed after 25-30 spools of mostly PETG printing.

Normal?

Well within normal range - if you're printing a lot of bright white (which is often colored with titanium dioxide, it's pretty abrasive) you can kill a nozzle in 5 rolls or so.

Under-extrusion along with the pressure extruding around a somewhat loosened nozzle would indicate a clog, so that would be one thing. If the bowden tube inside the hot end is degrading, it's a good time to sort that out.

Sometimes letting the nozzle cool and pulling out the hardened plastic while it's still a little warm pulls out nearly all of the plastic in the tip, along with whatever is obstructing it, but they're cheap enough, and after 25+ rolls you got your money's worth.

Yeah, my project before this was a 3ft long Star Destroyer done in white. I didn't realize colors had such an effect. I knew the wood/metal/stone filaments caused problems but I have been intentionally avoiding then.

Doing more terrain stuff with what's left of my filaments before the fresh shipment gets here. My son is getting a giant dragon bust using 3 different dual-tone PLAs.

"Hardened" nozzles from Amazon can range from okay to awful. Eyeballing from your picture it looks like it's a pretty standard Mk8 nozzle, so decent nozzles from other printer vendors (like Creality, seems commonly available) will work. DT-Swiss makes plated nozzles that are a fair bit more resilient (and more dimensionally accurate/better quality), but unless you know you're printing a lot of somewhat-abrasive filament it might not be worth the money.

Steel isn't worth it normally unless you're printing CF or metal fill, and because of the different heat conductivity requires some experimentation with some printer/filament combinations.

It's always a trade off between nozzle life and time between clogs.

Get either a Slice Vanadium nozzle or a Bondtech CHT.

I don't really see a need for any nozzle outside of these two. A Vanadium nozzle will outlast the printer and CHT had extremely long life (easily hundreds of rolls) and has extremely high flow rates for a hardened nozzle, even surpassing brass nozzle flow rates.

I had not looked at Bondtech in a long time, thanks for reminding me.