Tengu format ruling
Arcana Force XIV - Temperance

Card effect (current official text)During damage calculation, in either player's turn: You can discard this card; you take no Battle Damage from that battle. When this card is Summoned: Toss a coin and apply this effect. The effect lasts while this card is face-up on the field.
● Heads: Halve all Battle Damage you take.
● Tails: Halve all Battle Damage your opponent takes.
Rulings
(1) During either player's turn, you can discard this card to reduce the damage you take from a battle to 0. (2) When this card is Summoned, toss a coin. ● Heads: Halve all Battle Damage you take. ● Tails: Halve all Battle Damage your opponent takes.
- The (1) Quick Effect activates & resolves in the hand.
- Discarding this card is a cost.
- This effect is activated in Substep 4 - Damage Calculation.
- The (2) Trigger Effect is mandatory, it activates & resolves on the field.
- When this effect resolves, this card gains the corresponding Effect. The corresponding effect can be negated by Skill Drain, but this card will not forget which effect is gained while face-up.
- The (HEADS) Continuous Effect applies while this card is face-up on the field.
- This effect applies in Substep 4 - Damage Calculation, even if this card is destroyed by battle.
- The (TAILS) Continuous Effect applies while this card is face-up on the field.
- This effect applies in Substep 4 - Damage Calculation, even if this card is destroyed by battle.
Rulings data courtesy of Format Library — formatlibrary.com. Spotted an inaccuracy? Flag it in the Tengu forum — sourced change requests get reviewed.