what have you burned in your "noob days"

Siegfried, NP5 Darius, Gawain and Arjuna. I regret all except Gawain

>2 copy of astolfo
Say hi to Lucifer when you reach hell, thanks.

Gilgamesh during the NA game release a couple years back. Not understanding his rarity at the time, I thought it'd be funny to burn the card of the so called 'King of Heroes'. I hate myself till this day.

I burned some 5* CEs like K-scope because I didnt know you could MLB.

When I started out (like one month into the game), I fed Angra Mainyu to Gilgamesh, completely unaware of his rarity and meme status. I sorta kinda regret it but also not really lol.

Burned Medusa Lancer. Also burned Fionn when he spooked me on Enkidus banner. Almost burned Sanzang when she spooked me on the same banner but I'm glad I didn't.

Aaaand I pulled Nightingale on the GSSR, the one Berserker I didn't want, and I was so heartbroken I immediately went to burn her for prisms, oops. ;/

I've never burned a 4/5* of anything, servant or CE. Don't get enough of them to have ever really been tempted :)

Burned a lot of 4* already. Mostly for Rare Prisms, sometimes because I just couldn't stand to see another copy of them. There were...
... 2 Siegfrieds (have him still NP5 by now; back then he was NP4)
... 2 Sthenos (she's still NP4)
... 1 Fionn (he's NP2 and I honestly regret it more, that I didn't burn his second copy)
... Elizabeth, Astolfo and Carmilla (I got those three in two ten rolls. None of them is NP5, but I really wanted the Fate/Zero Mystique Code. Don't really regret it)

Until now I burned one 5* and that was Nicola Tesla.
I got him on the GSSR Banner last September I think it was. Didn't want him at first and didn't even need him. I already had Archuria and Arjuna. Still kept him a long while without leveling, because other Servants had higher priority.
When the Anniversary Blonde Mystique Code came into Rare Prism shop I took my chance and burned him.
Well, I wasn't well informed and thought because of the demerit on his NP he is a really bad Servant...
Part of me regrets it.

A little while later I got Orion/Artemis and also thought of burning him/her. Didn't do it. Have her Lv. 90 now. Don't use her at all. Still glad I have him/her.

sanzang cuz she wasn't foxy or waver my first week playing during a class summoning.
book-chan for same reason as sanzang
rama cuz idk why during a yolo roll in story my first week as well.
beowolf twice cuz i started with herc and had zerkerlot as my berzerkers
fionn twice cuz i heard he sucked... don't regret it.
karna for sheer salt of him being the 10th card of my last possible attempt for shishou.

Ive burnt media lily, helena and two copiea of nursery rythme, I only regret burning nursery rythme since ive got a waver anyway, and due to her np charge and AOE it would have been very helpful for farming

The only non-duplicate I've burned is Li Shuwen

Also burned a duplicate heroine x alter

Burned Artoria og saber
Because at first day valentine banner rate up and it was rainbow and I thought that will be definitely bride but luck give me her instead.
Not regret it because already have another copy of her and of course alter version.

2 copies of d’eon and 3 copies of Irisviel

I haven’t burnt any servants unless I have them np5 already, and only then it was some silver servants only.

What I regret was limit breaking some 4* and 5* CEs like innocent maiden and ideal king before being able to MLB them (and honestly I would now want at least 7 copies of Ideal king now).