Borderland Explorer — ruling 1

Players decide whether or not they’re discarding a card in turn order. Each player will know if previous players are discarding, but not what they are discarding. All cards to be discarded are set aside, then revealed and discarded simultaneously. Similarly, all basic land cards searched for are set aside, then revealed simultaneously.

Borderland Explorer : règles, fonctionnement et interactions (MTG)

Borderland Explorer is one of those cards players keep asking about. Here is, in plain words, what its official text says, the rulings published by Wizards of the Coast, and the combos players actually run.

Official card text

When this creature enters, each player may discard a card. Each player who discarded a card this way may search their library for a basic land card, reveal it, put it into their hand, then shuffle.

How it works : Borderland Explorer

Original English text — Wizards of the Coast / Scryfall

#1August 23, 2016· Wizards of the Coast
Players decide whether or not they’re discarding a card in turn order. Each player will know if previous players are discarding, but not what they are discarding. All cards to be discarded are set aside, then revealed and discarded simultaneously. Similarly, all basic land cards searched for are set aside, then revealed simultaneously.
No other card is named in this ruling.