Okay... what is this? Is it a hint to a new game mode or did I miss something?

https://i.imgur.com/MznjSvR.png I was making a new item set when I saw this... Translation: 1000 HP 1000 mana 500% base HP regen 500% base mana regen 150 armor 150 magic resist 500 AP 250 AD 200% atk speed 100% critical hit chance 40% life steal 40% movement speed 40% cooldown reduction

The item is NOT available in the following maps: Summoners Rift Howling Abyss Twisted Treeline