Soulherder — ruling 1

If any other abilities you control trigger at the beginning of your end step, you choose the targets for all of them as they’re put onto the stack, and you choose the order they’re put onto the stack. For example, this means that you could exile a creature put onto the battlefield by an unearth ability (and then unearth’s delayed triggered ability won’t exile that creature), but you can’t target a creature that will be returned to the battlefield by another ability during your end step (such as Astral Drift’s delayed triggered ability).

Soulherder — ruling 2

Once the exiled creature returns, it’s considered a new object with no relation to the object that it was. Auras attached to the exiled creature will be put into their owners’ graveyards. Equipment attached to the exiled creature will become unattached and remain on the battlefield. Any counters on the exiled creature will cease to exist.

Soulherder — ruling 3

If a token is exiled this way, it will cease to exist and won’t return to the battlefield.

Soulherder — ruling 4

If a creature is exiled but ends up in another zone (most likely because it’s a player’s commander in the Commander variant), Soulherder’s first ability triggers.

Soulherder : règles, fonctionnement et interactions (MTG)

Soulherder 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

Whenever a creature is exiled from the battlefield, put a +1/+1 counter on this creature. At the beginning of your end step, you may exile another target creature you control, then return that card to the battlefield under its owner's control.

Complete guide

Soulherder is a powerhouse in any deck built around creatures with 'enters-the-battlefield' abilities. This ghostly Spirit grows larger every time a creature leaves the battlefield for the exile zone and provides a free flicker effect every single turn.

Growing Through Exile

Soulherder has two distinct abilities. The first is a triggered ability that puts a +1/+1 counter on it whenever any creature is exiled from the battlefield. This includes creatures exiled by its own second ability, spells like Swords to Plowshares, or even tokens that are exiled. Note that if a creature is exiled but ends up in the Command Zone instead, Soulherder still gets its counter.

The End Step Flicker

At the beginning of your end step, you may choose another target creature you control to exile and immediately return to the battlefield. This 'flicker' effect causes the creature to be treated as a brand-new object. It will enter the battlefield again, triggering any 'enters' abilities it has. However, it loses any counters it previously had, and any Auras attached to it are put into the graveyard.

Timing and Tokens

Because the flicker happens at the beginning of your end step, you can stack this ability with other end-step triggers you control. A common mistake is targeting a creature token; if a token is exiled by Soulherder, it ceases to exist immediately and will not return to the battlefield. Additionally, you cannot target Soulherder with its own ability since the text specifies 'another' target creature.

Interaction examples

Ramping Every Turn

Solemn Simulacrum

With both on the battlefield, at the beginning of your end step, you target Solemn Simulacrum with Soulherder's ability. The Golem is exiled, which triggers Soulherder's first ability to gain a +1/+1 counter. Then, Solemn Simulacrum returns to the battlefield immediately. Its 'enters' ability triggers, allowing you to search for another basic land card every single turn.

Double the Spirit Energy

Roaming Throne

If you name 'Spirit' as Roaming Throne enters, it will interact with Soulherder. When you exile a creature during your end step, Soulherder's first ability triggers twice, giving it two +1/+1 counters. Furthermore, Soulherder's end-step ability itself triggers an additional time because of the Throne, allowing you to exile and return two different creatures (or the same creature twice, though the second trigger would resolve on the 'new' object) to maximize your value.

Guide written with AI from the official text and rulings. Official English text prevails.

How it works : Soulherder

Original English text — Wizards of the Coast / Scryfall

#1June 14, 2019· Wizards of the Coast
If any other abilities you control trigger at the beginning of your end step, you choose the targets for all of them as they’re put onto the stack, and you choose the order they’re put onto the stack. For example, this means that you could exile a creature put onto the battlefield by an unearth ability (and then unearth’s delayed triggered ability won’t exile that creature), but you can’t target a creature that will be returned to the battlefield by another ability during your end step (such as Astral Drift’s delayed triggered ability).
No other card is named in this ruling.
#2June 14, 2019· Wizards of the Coast
Once the exiled creature returns, it’s considered a new object with no relation to the object that it was. Auras attached to the exiled creature will be put into their owners’ graveyards. Equipment attached to the exiled creature will become unattached and remain on the battlefield. Any counters on the exiled creature will cease to exist.
No other card is named in this ruling.
#3June 14, 2019· Wizards of the Coast
If a token is exiled this way, it will cease to exist and won’t return to the battlefield.
No other card is named in this ruling.
#4June 14, 2019· Wizards of the Coast
If a creature is exiled but ends up in another zone (most likely because it’s a player’s commander in the Commander variant), Soulherder’s first ability triggers.
No other card is named in this ruling.