Trusty Mountain Yak

The Animal Courier is an item purchasable at the Main Shop, under Consumables. It creates a small fast unit that can carry you and your allies' items to and from your base. If it dies it will respawn after three minutes, and the items it was carrying will be inaccessible until then. Can be upgraded to a Flying Courier.

Summon Animal Courier
Summons an Animal Courier to carry items for you. The Animal Courier is not affected by most spells, and has magic immunity. It gives 175 gold to each enemy player if killed. The courier is invulnerable when near the friendly Fountain. It can use some items that cost no mana, being able to use Healing Salve and Clarity on heroes (but not on itself), Tangoes and the Smoke of Deceit which will provide the shroud effect to any allied heroes in close proximity to the Courier.

Summon Flying Courier
Summons a Flying Courier to carry items for you. The Flying Courier is not affected by most spells, and has magic immunity. It gives 175 gold to each enemy player if killed. The Flying Courier is invulnerable when near the friendly Fountain and will instantly die if it is too close to the enemy fountain area. It can use some items that cost no mana, being able to use Healing Salve and Clarity on heroes (but not on itself), Tangoes and the Smoke of Deceit which will provide the shroud effect to any allied heroes in close proximity to the Flying Courier.