Bound in Silence

Official rulings

1. If you put Bound in Silence onto the battlefield without casting it, perhaps using the "recruiting" ability of a card like Amrou Scout, it will enter attached to a creature. You choose that creature as you're putting the Aura onto the battlefield. This doesn't target that creature, so you could have it enter the battlefield attached to a creature an opponent controls with hexproof, for example. If there's no creature on the battlefield it can be attached to, it stays in whatever zone it was in. (2021-03-19)
2. If Bound in Silence becomes attached to a creature that's already attacking or blocking, the creature continues to attack or block as normal. (2021-03-19)
3. This cards was originally printed with the "tribal" card type. That card type has been replaced with "kindred". This change does not affect the gameplay function of this card. (2024-06-07)
4. While it appears only on cards that already have other card types, kindred is a card type and will be counted by effects that refer to the number of card types among cards in a zone. (2024-06-07)
5. Kindred is a card type that allows noncreature cards to have creature types. For example, Echoes of Eternity is an Eldrazi (although not a creature) while on the battlefield and an Eldrazi card (although not a creature card) in zones other than the battlefield. (2024-06-07)