Stonewall Impasse

When this defends, clash with the attacking hero. If you win, this gets +1

until end of turn.

Temper

Rulings

From the Heavy Hitters release notes

You only win if you reveal the card with the greatest . If you reveal a card with the same or less than the attacking hero, or reveal a card with no , you don’t win the clash.
When resolving this equipment’s temper trigger, it will be destroyed if it has 0 after all modifications have been applied, including the increase from winning the clash for this equipment’s when you defend trigger.

Keyword notes

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.

If the equipment gains a -1 in a different way other than defending, it would not be destroyed even if it has 0.

All keywords

Clash - Clashing heroes reveal the top card of their deck. The hero that reveals the card with greatest {p} wins.

Clash is an effect keyword.
Effects that modify values of cards in your deck are considered when clashing (e.g. Kayo, Mutated Mass, etc.)
If you win a clash, the opponent is considered to have failed to win the clash.
If no one wins a clash, you’re both considered to have failed to win the clash.
If both you and the opponent reveal a card with the same , no one wins the clash.
If both you and the opponent reveal a card without and/or don’t reveal any card, no one wins the clash.
If you reveal a card with and the opponent reveals a card without , you win the clash.
If you reveal a card with and the opponent doesn’t reveal any card, you win the clash.