Invalid or absent target
On Android Arena, Jace the perfected mind allows the use of his plus one ability, "until your next turn up to one target creature gets -3/-0" even if there is no target available. According to CR 115 a spell or ability has to have a legal Target in order to trigger or be cast.
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Endrasalem#53653
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Rezzahan#77802
commented
That's why Jace's ability says "up to one", which includes the choice of zero targets.