Renegade Rallier — ruling 1

A permanent card is an artifact, creature, enchantment, land, or planeswalker card.

Renegade Rallier — ruling 2

The mana value of a card in your graveyard is determined solely by the mana symbols printed in its upper right corner. The mana value is the total amount of mana in that cost, regardless of color. For example, a card with mana cost {1}{U}{U} has mana value 3.

Renegade Rallier — ruling 3

If a card in your graveyard has no mana symbols in its upper right corner (because it's a land card, for example), its mana value is 0.

Renegade Rallier — ruling 4

If the mana cost of a card in your graveyard includes {X}, X is considered to be 0.

Renegade Rallier — ruling 5

You can target any permanent card in your graveyard with mana value 2 or less, not just one that was put there from the battlefield this turn.

Renegade Rallier — ruling 6

Revolt abilities check only whether a permanent you controlled left the battlefield this turn or not. They don't apply multiple times if more than one permanent you controlled left the battlefield. They don't check whether the permanent that left the battlefield is still in the zone it moved to.

Renegade Rallier — ruling 7

Revolt abilities don't care why the permanent left the battlefield, who caused it to move, or where it moved to. They're equally satisfied by an artifact you sacrificed to pay a cost, a creature you controlled that was destroyed by Murder, or an enchantment you returned to your hand with Leave in the Dust.

Renegade Rallier — ruling 8

Tokens that leave the battlefield will satisfy a revolt ability.

Renegade Rallier : règles, fonctionnement et interactions (MTG)

Renegade Rallier 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

Revolt — When this creature enters, if a permanent left the battlefield under your control this turn, return target permanent card with mana value 2 or less from your graveyard to the battlefield.

How it works : Renegade Rallier

Original English text — Wizards of the Coast / Scryfall

#1February 9, 2017· Wizards of the Coast
A permanent card is an artifact, creature, enchantment, land, or planeswalker card.
No other card is named in this ruling.
#2February 9, 2017· Wizards of the Coast
The mana value of a card in your graveyard is determined solely by the mana symbols printed in its upper right corner. The mana value is the total amount of mana in that cost, regardless of color. For example, a card with mana cost has mana value 3.
No other card is named in this ruling.
#3February 9, 2017· Wizards of the Coast
If a card in your graveyard has no mana symbols in its upper right corner (because it's a land card, for example), its mana value is 0.
No other card is named in this ruling.
#4February 9, 2017· Wizards of the Coast
If the mana cost of a card in your graveyard includes , X is considered to be 0.
No other card is named in this ruling.
#5February 9, 2017· Wizards of the Coast
You can target any permanent card in your graveyard with mana value 2 or less, not just one that was put there from the battlefield this turn.
No other card is named in this ruling.
#6February 9, 2017· Wizards of the Coast
Revolt abilities check only whether a permanent you controlled left the battlefield this turn or not. They don't apply multiple times if more than one permanent you controlled left the battlefield. They don't check whether the permanent that left the battlefield is still in the zone it moved to.
No other card is named in this ruling.
#7February 9, 2017· Wizards of the Coast
Revolt abilities don't care why the permanent left the battlefield, who caused it to move, or where it moved to. They're equally satisfied by an artifact you sacrificed to pay a cost, a creature you controlled that was destroyed by Murder, or an enchantment you returned to your hand with Leave in the Dust.
No other card is named in this ruling.
#8February 9, 2017· Wizards of the Coast
Tokens that leave the battlefield will satisfy a revolt ability.
No other card is named in this ruling.
#9February 9, 2017· Wizards of the Coast
Energy counters aren't permanents. Paying won't satisfy a revolt ability.
No other card is named in this ruling.
#10February 9, 2017· Wizards of the Coast
All cards in the Aether Revolt set with triggered revolt abilities use an intervening "if" clause. A permanent you controlled must have left the battlefield earlier in the turn in order for these abilities to trigger; otherwise they do nothing. In other words, there's no way to have the ability trigger if no permanent you controlled has left the battlefield that turn, even if you intend to have one do so in response to the triggered ability.
No other card is named in this ruling.