No. If a spell truly requires a specific target, without saying something like "up to one target...", you can't cast it without a legal target for that targeting instruction.
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I'm a former judge (lapsed), who keeps up to date on rules and policy. Keep in mind that judges' answers aren't necessarily more valid than those of people who aren't judges; what matters is we can quote the rules to back up our answers. When in doubt, ask for such quotes.
You can't cast Searing Blaze if you can't have it target both—
a player or planeswalker, and
a creature controlled by that player or that planeswalker's controller
(C.R. 108.1, 115.1a, 601.2, 601.2c).
As a result, you can't cast Searing Blaze targeting an opponent unless that opponent also controls a creature.
Note that Searing Blaze can target any "player or planeswalker", including you or a planeswalker you control, as long as that player or that planeswalker's controller also controls a creature (C.R. 108.1, 115.1a).
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As a result, you can't cast Searing Blaze targeting an opponent unless that opponent also controls a creature.
Note that Searing Blaze can target any "player or planeswalker", including you or a planeswalker you control, as long as that player or that planeswalker's controller also controls a creature (C.R. 108.1, 115.1a).
Nexus MTG News // Nexus - Magic Art Gallery // MTG Dual Land Color Ratios Analyzer // MTG Card Drawing Odds Calculator
Want to play a UW control deck in modern, but don't have jace or snaps?
Please come visit us at the Emeria Titan control thread