Arboria

Creatures can't attack a player unless that player cast a spell or put a nontoken permanent onto the battlefield during their last turn.

As the world steeled itself for the New Phyrexian invasion, the heart of the Pinelands awoke, and a new maro-sorcerer strode forth to join the fight.

Dominaria Remastered

"I have never before felt so unwelcome in a forest."
—Jolrael

Masters Edition III

Creatures can't attack a player who didn't cast a spell and didn't put a card onto the battlefield during his or her last turn.

Legends

If a player does not cast a spell or put a card into play on his or her turn, no creatures may attack that player until after his or her next turn.

Arboria doesn’t stop creatures from attacking planeswalkers, regardless of what their controllers did or didn’t do during their last turns.

Arboria’s effect cares about the actions taken by players, not their results. If a player cast a spell during their last turn but that spell was countered, that player may still be attacked. The same is true if a player put a nontoken permanent onto the battlefield during their last turn, but that permanent left the battlefield before their turn ended.

Arboria’s effect cares whether a player put a nontoken permanent onto the battlefield. It’s unusual for an ability to care who put a permanent onto the battlefield, as opposed to under whose control it entered.

If two or more permanents have the world supertype, all of them are put into their owners’ graveyards except the one that has had the world supertype for the shortest amount of time. If there’s a tie for the shortest amount of time, all world permanents are put into the graveyard.