Scroll of Isildur

Each time the Ring tempts you, you must choose a creature if you control one.

Some spells and abilities that cause the Ring to tempt you may require targets. If each target chosen is an illegal target as that spell or ability tries to resolve, it won't resolve. The Ring won't tempt you.

If Scroll of Isildur leaves the battlefield or you lose control of it before its first chapter ability resolves, control of the target artifact doesn't change at all.

If the target is not legal as Scroll of Isildur's first chapter ability tries to resolve, the ability is removed from the stack. The Ring won't tempt you.

If the creature you choose as your Ring-bearer was already your Ring-bearer, that still counts as choosing that creature as your Ring-bearer for the purpose of abilities that trigger "whenever you choose a creature as your Ring-bearer" or abilities that care about which creature was chosen as your Ring-bearer.