It takes about 80 hours to beat the Elite four and claim your crown as champion Pokemon trainer. Then you'll need to do some clever trading/buying/soul selling to catch all of the game's Pokemon, which is probably as big a task if not greater. And then you must do the same for all the old pokemon from other regions.
When you do finally complete your Pokedex and wait for something special to happen, nothing does. Nothing.
Now, we wouldn't say you've wasted a huge chunk of your life because we understand how important this gaming achievement is to anyone who considers themeslves a serious gamer. Or a seven-year-old. But… it would have been nice for the game to recognise it. Put it this way, if the game itself doesn't congratulate you, who else is going to? Your girlfriend? Er... she left days ago.
You did notice, didn't you?
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