Worst trades you've made

[Vyse]

I've made some pretty bad trades/sales before. Before  {Thundermaw Hellkite} hit its peek I didn't want mine, I didn't play much red, and put it on e-bay for 15 dollars. It sold for 18 TT. How about you guys?

[Bozo_Law]

A bunch of werewolves for a snapcaster when I was a noob. Worst decision ever lol

[All-Mana Mania]

My bro sold a foiled jace thr mind sculptor for $50

[Silent1236]

The first that springs to mind for me was when I was still kinda new, I traded a {Batterskull} for an {Etched Monstrosity}. 

[Birdbrain]

The first that springs to mind for me was when I was still kinda new, I traded a {Batterskull} for an {Etched Monstrosity}.

i want to make the monstrosity work on a deck

[Quackmaster5]

The first that springs to mind for me was when I was still kinda new, I traded a {Batterskull} for an {Etched Monstrosity}.

i want to make the monstrosity work on a deck

Works great in either a counter  {Varolz, the Scar-Striped} themed deck or a  {Melira, Sylvok Outcast} persist deck.

[Kagain123]

I had quit MtG right after future sight came out. Got back in when Shards hit and traded a  {Tarmogoyf} for a  {Lich's Mirror} still thinking goyf was worth $1 which is what it was worth when I got out. Still kicking myself about it though I did get the last laugh. The shop I traded it to closed less than 3 months later.

[Monrodesign]

 {Sphinx's Revelation} for {Garruk, Primal Hunter} before sphinx jumped to $20.oo+

[Kareason]

I sold my entire collection, that started in Alpha/Beta and ended with some Weatherlight, for $300 the first time I quit.  Current value would pay my mortgage for a couple years at least.

[Frothandslosh]

I traded away some of my Zendikar rares, like {Bloodghast}, {Verdant Catacombs}, and {Eye of Ugin}, for a bunch of Yugioh cards when I got back into the game.

[MisterJH]

Not that bad compared to some, but i traded 2 shocks for {sublime archangel} right before she dropped... A lot

[MuggyWuggy]

I traded a shock for an empty envelope.

[Moneekahh]

My fiancé traded 2  {Æther Vial} and 2  {Show and Tell} when he got back into magic for some alarm block crap like  {Mayael the Anima} and friends!

[Death Gaara]

I sold my 5 Jace, The Mind Sculptors for around $60 each before they first jumped to $100. I also sold my playset of Cliques before modern was announced for around $25. There are many more, but those are just a few cases.

[Falcon182]

I traded a ton of legends and revised stuff including 6 or 7 dual lands for a bunch of Star Wars TCG booster packs... Obviously kicking myself now but at the time it seemed like a solid deal. Haha