Testament: Mechanics

Vengeful: Used on 0 cards:

Ability word, checks if a permanent you controlled left the battlefield. Near-identical to Revolt, rebranded for flavor and revolt cards check end of turn or on cast, this triggers every time the condition is met. In abzan.

Envy: Used on 0 cards:

Ability Word, Ability happens whenever an opponent draws a card. in Jeskai.

Rebound: If this spell was cast from your hand, instead of putting it into your graveyard as it resolves, exile it and, at the beginning of your next upkeep, you may cast this card from exile without paying its mana cost. Used on 0 cards:

Returning mechanic, in Temur. Colors also care about Second Spell each turn, strong synergy.

Golem Tokens: Golems are 2/2 Artifact creature tokens with " {t}

, Sacrifice this creature: Add {c}

" Used on 0 cards:

Redeem: Pay PARAM1 and discard this card to return target permanent with converted mana cost less than this abilities cost to the battlefield. Redeem only as a sorcery. Used on 0 cards:

Recursion mechanic, turns any spell that has it into a possible grave outlet. Technically in Mardu, Not sure if Red should or should not have it. The set is modeled after earlier days of the color pie, and red does have an amount of recursion from those times, but it probably feels too weird for modern players.

In card text or details pages, write the mechanic's code name (playtest name) between square brackets, like "[Crittercast]", "[Bushido 1]" or "[Delay 4 {2}{R}{R}]". It will be expanded to the mechanic's name plus reminder text, such as "Suspend 4 – {2} {r} {r} . (Rather than cast this spell from your hand,...)"
To expand a mechanic's name but not its reminder text, include parentheses at the end of the square brackets: "[Crittercast()]", "[Delay 9 {R}()]".