Note: This requires you to have another wow licence which has not been upgraded to legion on your main battle.net account in order for it to work (non-starter) so this guide does not factor in purchasing the WoW licence required if you do not already have this, although this will still be cheaper than buying a boost directly from the store.
It is possible to get a level 100 character boost for about half the price of what it would cost you if you bought a boost directly from the in-game store.
You will need to have a second wow licence on your battle.net which has not been upgraded to legion, if you do not already have a second licence, you can easily add one by going to your battle.net account page and add a starter edition licence once you have this, purchase legion somewhere cheap usually around 25 euros / 27 dollars, see below link for a small list of digital licences you can buy for a cheap price (it's not a referral link so don't worry)
EU: Buy WoW Legion CD KEY Compare Prices
US: WoW Legion Digital Download Price Comparison
Once you have a legion key, redeem it on your second wow licence on your battle.net account and log into the game.
You can then claim that character boost on your main account, as the 100 boost the Token is BATTLE.NET BOUND and usable on EVERY ACCOUNT on the Battle.net.
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