Here are the new decay rules for Challenger and Master tier

With lax decay rules at the top of League’s ladder, a funny thing happened recently: the players at the top simply weren’t playing that often, and many players instead had multiple high-level accounts they would switch between. At the time of this writing, the player at the top of the ladder, Team Liquid jungler Lyonel "Arcsecond" Pfaender, had played three games in the past month on his No. 1 Challenger account.

For those unfamiliar, decay happens to your high-level ranked account if you don’t play on it for a while, removing you from the standings and taking away LP. Previously, decay only happened if your account was inactive for 28 days. That’s still the case for Platinum and Diamond accounts, but there’s a new rule for Master and Challenger players with the release of Patch 6.18.

DEPOSIT ACCOUNTS Players can play to store up to 10 banked games of decay immunity

MAINTENANCE FEES Each day, 1 banked game is removed from player reserves

INACTIVITY PENALTIES Starting when the number of banked games first reaches 0, players incur 100 points of LP decay per day until they bank additional games of decay immunity

ACCESS YOUR STATEMENTS ONLINE Banked games are tracked on the Leagues tab

tl;dr If you’re a Master or Challenger player, you want to be playing every day now (unless you have a bunch of banked games stored).