This means that your newly purchased product that sentence is aimed at was a disastrous mistake to buy.

The sentence is used originally for those who bought Shogun 2, and were suprised by the shitty game. Later on, they would use it for any failured purchases.

¨I bought this new game for 55 bucks, it became a shogun¨

¨I hope this new game isn't going to be a shogun¨
Shogun It became a Shogun! Shitty game
by FromSweden November 24, 2011
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