Gauntlets of Unity

Unity - When this defends together with a card from hand, this gets +1

until end of turn.

Temper

Rulings

From the Compendium of Rathe release notes

To defend together with a card, this must become a defending card at the same time as the other card. This can either be done by the defending hero declaring both cards during the defend step of combat, or by an effect that puts both of the cards onto the chain link as defending cards at the same time.
You typically can only defend with an equipment (with a defense value) once per combat chain, but the effect lasts until the end of the turn.
Each time you defend together with Gauntlets of Unity in the same turn it gains an additional +1 defense until end of turn, but will get an -1 counter after each time the combat chain closes.

Keyword notes

Unity - Unity – When this defends together with a card from hand, […]

Unity is an ability label keyword.
To defend together with a card, this must become a defending card at the same time as the other card. This can either be done by the defending hero declaring both cards during the defend step of combat, or by an effect that puts both of the cards onto the chain link as defending cards at the same time.

All keywords

Temper - Temper is a new keyword that exists on equipment in Crucible of War. Usually high in defense, Temper equipment presents a choice when it is down to 1{d}, of whether to defend with it one last time and see it destroyed, or save it to use for its ability.