World of warplane offer extremely cheap bundle to SA server(those who registered in SA, physically, or via VPN)
The bundle is nothing but huge load of free exp and gold, for example, for merely 40 USD, you can buy 30k gold and 500k free exp; for 150 USD, you can buy 130k gold and 2.6m free exp, AND they can be used in WOT directly because WOT and Warplane's gold and free exp are shared.
Due to this terrible (or should I say smart) marketing attempt, you now see large amount of accounts in NA server, who merely have <500 battles, but own multiple tier X, they are either some very terrible players with 400ping from Brazil, or some edgy rerolls. In case you wonder why tier X experience in NA servers are so bad, here is the answer.
edit: for those who wondering, it's GYRFALCON TROPHIES, they are extremely cheap if your account is registered in Argentina region, only 1/5 of the price comparing to US dollar. Unlike WOT or Warship lootboxes, these warplane boxes give a large amount of gold and free exp, and they can be shared in WOT/Warships.