When you see certain YuGiOh cards that are just too good of a deal (i.e. Sacred Beasts, Gods, Ultimate Rares, Chimeratech, Stein, Cyber Dragon, etc...) and they're really low priced, look for a few things:

1: Check the seller's rating and positive percentage (but don't reply solely on the seller because I've been sold a LOT of items by honest people that just either didn't know what they had or didn't know it was a fake card)

2: See if the picture of the card is the real picture, or a stock photo. (stock photo is usually obtained from a website or someone else's auction)

3: Look to see if the seller actually states the condition and where it is made. (i.e. Is it UDE made?  Is it 1st Edition or Unlimited version?  Is it mint, near mint, good, fair or poor condition?  Is it made in the USA, Europe, Australia, Germany, Japan, etc...)

4: Look at the font on the card if it's a picture of the actual card!!!  This is VERY important.  (i.e. I received a fake Cyber-Stein once and when I got it, I noticed that it was fake.  It was a very GOOD fake, but still fake.  The "5" in "5000" was off.  And the "DB2-EN100" was just a little different.  Then I noticed that "N" in "STEIN" was too high.  There were many more things, but this is important too.... the white, faded edges around the black border of the card was missing.  And the burnt-orangish color on the back of the card was WAY too dark)  These are just some basic ideas on how to tell a fake card from a real card.  #1 is look at the font.  That's where they always screw up.  #2 is double-check the UDE holographic logo on the bottom-right hand part of the card.  If it's real, then don't forget to check it's location.  The top-left hand part of the square MUST just barely touch the bottom-right hand part of the effect/description square.  (look at your real cards and you'll see what I mean)

5: The God cards are the #1 most frequently made fake cards!  There are 3 versions of the REAL ones.  There are: GB1 (Secret Rare), GB1 (Ultra Rare) and then they reprinted each God card in a seperate Promo set.  Here is those numbers: Ra (DOD), Obelisk (JMP) and Slifer (YMA).  HOWEVER, most sellers that sell the fake ones reprint the Ultra Rare GB1 set.  So what you need to do is closely read my #4 rule over and over until you're sure they're real Gods.  Second, ask the seller BEFORE you bid!!!  That's VERY important.  If they tell you that they're real, then you can have proof in an email to use against them at a later time with either Ebay, Upperdeck/Konami or even the courts. (Court sounds a little extreme, but do you want to get your money back or not?)

6: If you receive a fake card, do NOT leave negative feedback right away.  Contact the seller and explain why you think it's a fake.  Take LOTS and LOTS of digital pictures with different lighting and at different angles.  Because if you send the card back to get your refund, then you have no proof that it was the one that you sent back.  They can say that you were lying.

Feel free to contact me for any questions.  Good bidding and happy hunting!