Shanna, Purifying Blade
Legendary Creature — Human Warrior
Lifelink
At the beginning of your end step, you may pay 
. If you do, draw X cards. X can't be greater than the amount of life you gained this turn.
Jody Clark
Dominaria United (DMU)
• #317Rulings
You choose the value for X as the ability resolves.
(wotc • 2022-09-09)
Rulings
You choose the value for X as the ability resolves.
(wotc • 2022-09-09)