The +1 loyalty counter is put on Liliana as a cost, so it happens while you are activating the ability, and thus it's there before any player can even respond. And yes, the ability does fizzle due to no longer having any legal targets. (Due to a somewhat recent rules change, that now means it resolves doing nothing rather than being countered on resolution.) The "up to one target" matters when you activate the ability, since that is when you choose targets, and thus is when you have to choose the number of targets. If you activate an ability or cast a spell with "up to X targets", you determine and lock in the number of targets at that time. The spell/ability then is a spell with exactly X targets and is handled like any other such spell.
Edit:
The "up to one" in Liliana's +1 ability also means, that you can activate the ability without targeting any creature, even if a targetable one is around, by choosing zero targets.
So if i control a liliana the last hope, and i +1; target a guy, what would happen if my opponent sacs it in response?
Does the ability fizzle 'cuz all the targets are gone? Or does it, because it says "up to one target", still resolve? Does liliana still get to +1?
Legacy - Solidarity - mono U aggro - burn - Imperial Painter - Strawberry Shortcake - Bluuzards - bom
The +1 loyalty counter is put on Liliana as a cost, so it happens while you are activating the ability, and thus it's there before any player can even respond. And yes, the ability does fizzle due to no longer having any legal targets. (Due to a somewhat recent rules change, that now means it resolves doing nothing rather than being countered on resolution.) The "up to one target" matters when you activate the ability, since that is when you choose targets, and thus is when you have to choose the number of targets. If you activate an ability or cast a spell with "up to X targets", you determine and lock in the number of targets at that time. The spell/ability then is a spell with exactly X targets and is handled like any other such spell.
Edit:
The "up to one" in Liliana's +1 ability also means, that you can activate the ability without targeting any creature, even if a targetable one is around, by choosing zero targets.
Former Rules Advisor
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