>>45579970DeNA used to run a game called Hellfire. It was a typical gacha game with a fairly standard PvE gameplay with increasing single player difficulty to encourage you to pull. They eventually started adding raid events where you fought an undefeatable enemy with a time limit. The more damage you dealt in a single attempt and the more total damage you dealt throughout the event, the higher your score on the leaderboard and the better rewards you received.
At first this favoured anyone who farmed up or lucked out on the best units, but then they changed it so special event units got enormous bonus stats when fighting the event boss, so only the whales that pulled for the rare units would be able to get the high scores and rewards. They increased the frequency of these events and their banners until it was a new one every couple of weeks and only the biggest of whales could keep up.
Then, in the middle of an event, within just 2 days of releasing a banner, they cut all support for the game, ended the event, and released the sequel, Hellfire: The Summoning. Just like that, all the whales had nothing. All the free players who stuck around had nothing. You couldn't even play the old game, you had to get the sequel and start from scratch. Everything, gone.
The sequel also shut down completely, in case you're wondering.