Splinter, Hamato Yoshi — ruling 1

If a creature spell's sneak cost was paid, the creature it becomes enters tapped and attacking the same player, planeswalker, or battle as the creature that was returned to its owner's hand to pay its sneak cost. This is a rule specific to sneak; in other cases, when a creature is put onto the battlefield attacking, that creature's controller chooses which player, planeswalker, or battle it's attacking.

Splinter, Hamato Yoshi — ruling 2

Although a creature put onto the battlefield this way is attacking, it was never declared as an attacking creature. Abilities that trigger whenever a creature attacks won't trigger when that creature enters attacking.

Splinter, Hamato Yoshi — ruling 3

Spells can only be cast for their sneak costs any time you could play an instant during the declare blockers step on your turn (after your opponent has decided whether to block).

Splinter, Hamato Yoshi : règles, fonctionnement et interactions (MTG)

Splinter, Hamato Yoshi 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

Sneak (You may cast this spell for if you also return an unblocked attacker you control to hand during the declare blockers step. He enters tapped and attacking.) Menace (This creature can't be blocked except by two or more creatures.) Other Ninjas you control get +1/+1.

How it works : Splinter, Hamato Yoshi

Original English text — Wizards of the Coast / Scryfall

#1January 27, 2026· Wizards of the Coast
If a creature spell's sneak cost was paid, the creature it becomes enters tapped and attacking the same player, planeswalker, or battle as the creature that was returned to its owner's hand to pay its sneak cost. This is a rule specific to sneak; in other cases, when a creature is put onto the battlefield attacking, that creature's controller chooses which player, planeswalker, or battle it's attacking.
No other card is named in this ruling.
#2January 27, 2026· Wizards of the Coast
Although a creature put onto the battlefield this way is attacking, it was never declared as an attacking creature. Abilities that trigger whenever a creature attacks won't trigger when that creature enters attacking.
No other card is named in this ruling.
#3January 27, 2026· Wizards of the Coast
Spells can only be cast for their sneak costs any time you could play an instant during the declare blockers step on your turn (after your opponent has decided whether to block).
No other card is named in this ruling.