99% of them are female, 80% of that 99% own either an already-known item (like they steal the MIllennium Rod from Malik or something) or the Millennium Item they own is completely made up (the Millennium Necklace or Millennium Bangle or Millennium Big Pretty Shiny Thing, for example.) 100% of them are unbeatable duelists. 100% of them are absolutely gorgeous. 95% of them act like airheads. 100% of them have pretty-love-and-peace decks.
I have yet to see a Mary-Sue use a card that could be considered 'weak' or 'dark' or 'odd' or 'un-aesthetic.' I have yet to see a Mary-Sue use a Doma the Angel of Silence. I have yet to see a Mary-Sue use a Beaver Warrior. I have yet to see a Mary-Sue use a Jirai Gumo. I have yet to see a Mary-Sue use something with less than 1000 attack power. I don't think I've ever seen a Mary-Sue use an actual magic or trap card. I've never seen a Mary-Sue with a 100% true-to-the-game deck, with no original cards in it.
And almost every Mary-Sue deck consists of pretty monsters. Strong, pretty monsters. Monsters who fight for love, peace, justice and the American way. Monsters who act like Sailor Scouts from Sailor Moon. Monsters whose names include "Hope" or "Friendship" or "Light" or "Love". They are all aesthetically pleasing. They are almost always dragons. Or Unicorns. Or Pegasi. Or some other pretty creature. pretty. Pink, white, light purple, silver. Pretty.
Not dark.
If they're going to make up their own deck, of COURSE they're not going to include cards like "Bloody Tears" or "The Crying Statue" or "The Beheaded Gorgon" (and I just copyrighted those cards, so steal 'em, and I'll steal your soul.) Nope. And of course, they're not going to include some weird-ass card like Frenzied Panda. Nor do they include actual cards, like Yami or Ultimate Offering. No. They will do nother that might jeopardize their beloved Pretty Pink Heart Dragon of Uber Super Mega Delicious Friendship Honeydew Ultra-Great Atomic Silver-Eyes ness. Of course the PPHDUSMDFHUGASEN is tof the 'Divine' element. So it doesn't have any weaknesses.
They're unbeatable. They could clean out Yugi, Pegasus, and Seto Kaiba within 3 rounds. They're child's play to them. And that's with the full, official 8000 starting life points. Let's not even go into how quickly they could smoke 'em at the anime's meager 2000 life points.
And it's just not right.
They don't get insulted, they fall in love with the main character immediately, and they're lke Mary Poppins. Except for one thing:
Mary Poppins was cool.
Despite the fact that Mary Poppins and Mary-Sues have the same first name, Mary-Sues suck, and Mary Poppins is cool.
Mary Poppins didn't play Duel Monsters.
