Backbone

Backbone is a MTG Arena-specific keyword ability that causes creatures to deal damage based on their toughness.

History
Backbone was introduced in the March 12, 2020 Game Update (1.06.00.00). According to Matt Tabak, the term will not be appearing on printed Magic cards now or in the foreseeable future.

Cards granting backbone

 * Arcades, the Strategist
 * Assault Formation
 * Belligerent Brontodon
 * Doran, the Siege Tower
 * Gauntlets of Light
 * High Alert
 * Huatli, the Sun's Heart
 * Solid Footing
 * Treefolk Umbra</c>
 * Weight Advantage</c>