Chinese tech giant Tencent became one of the world’s biggest videogame makers thanks to its 2011 acquisition of U.S. game studio Riot Games, maker of blockbuster “League of Legends.” But relations between the two companies have often resembled a war game, forcing Tencent to cut costly deals to keep Riot happy.

New details uncovered by The Information put a spotlight on how the two companies have clashed. In 2014, for instance, Riot was so dissatisfied with how Tencent was publishing “League of Legends” in China that it opened its own office in Hong Kong to try to take more control of the game. It quietly hired a former Tencent executive who once oversaw “League” in China to oversee China publishing—warning Riot employees to not talk about the hire to Tencent people.