Goat 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.

How it works : Goat

Original English text — Wizards of the Coast / Scryfall

No additional ruling has been published for this card.

Interactions with other cards

These cards' text mentions Goat.

Woe Strider

When this creature enters, create a 0/1 white Goat creature token. Sacrifice another creature: Scry 1. Escape—{3}{B}{B}, Exile four other cards from your graveyard. (You may cast this card from your graveyard for its escape cost.) This creature escapes with two +1/+1 counters on it.

Trading Post

{1}, {T}, Discard a card: You gain 4 life. {1}, {T}, Pay 1 life: Create a 0/1 white Goat creature token. {1}, {T}, Sacrifice a creature: Return target artifact card from your graveyard to your hand. {1}, {T}, Sacrifice an artifact: Draw a card.

Animal Sanctuary

{T}: Add {C}. {2}, {T}: Put a +1/+1 counter on target Bird, Cat, Dog, Goat, Ox, or Snake.

Contraband Livestock

Exile target creature, then roll a d20. 1—9 | Its controller creates a 4/4 green Ox creature token. 10—19 | Its controller creates a 2/2 green Boar creature token. 20 | Its controller creates a 0/1 white Goat creature token.

Clackbridge Troll

Trample, haste When this creature enters, target opponent creates three 0/1 white Goat creature tokens. At the beginning of combat on your turn, any opponent may sacrifice a creature of their choice. If a player does, tap this creature, you gain 3 life, and you draw a card.

Springjack Pasture

{T}: Add {C}. {4}, {T}: Create a 0/1 white Goat creature token. {T}, Sacrifice X Goats: Add X mana of any one color. You gain X life.

Goatnap

Gain control of target creature until end of turn. Untap that creature. It gains haste until end of turn. If that creature is a Goat, it also gets +3/+0 until end of turn.

Springjack Shepherd

Chroma — When this creature enters, create a 0/1 white Goat creature token for each white mana symbol in the mana costs of permanents you control.

Discordant Piper

When this creature dies, create a 0/1 white Goat creature token.

Goatnapper

When this creature enters, untap target Goat and gain control of it until end of turn. It gains haste until end of turn.

Everythingamajig

{1}, {T}: Scry 2. {1}, {T}, Pay 1 life: Create a 0/1 white Goat creature token. {7}, {T}, Sacrifice this artifact: Choose target player. At the beginning of the next end step, exchange life totals with that player, exchange control of all permanents you and that player control, and exchange cards in your hands, cards in your libraries, and cards in your graveyards.

The Grand Goatnapper

Spells you cast have affinity for Goats. {T}: Another target non-Goat creature perpetually becomes a Goat in addition to its other types. Then conjure a card named Goatnap into your hand. Activate only as a sorcery.