What it does
I'm not aware of "Sonic Booster" as an official Magic: The Gathering keyword or ability. It doesn't appear in the comprehensive rules or any released set that I can confirm.
It's possible this is a misremembered name, a custom/unofficial card, or something from a specific community or fan set (like Mythicwyrm's own homebrew content). If it's a Mythicwyrm-specific mechanic, I'd need the actual reminder text or card to explain it accurately rather than guess and risk giving you wrong rules information.
If you can share the card text or point me to where you saw it, I'll happily break down what it does, the rules nuance to watch for, and how it plays in Commander. Could you also double-check the spelling—it may be close to a real keyword like "Boast," "Surge," or an energy/amplify mechanic.
Iconic cards with Sonic Booster
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