Raphael's Technique

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.

A player may choose to discard their hand even if their hand contains zero cards.

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.