"Hyperphase Threshers" isn't a keyword or ability—it's a specific creature card. Hyperphase Threshers is an artifact creature (a Phyrexian construct) from the Warhammer 40,000 Commander decks, themed around the Necrons.
The card itself is fairly straightforward: it's a creature with stats and likely some combat-relevant ability fitting the Necron "Tyranid Swarm" or attrition theme, but it doesn't represent a reusable rules keyword the way deathtouch, flying, or menace do. If you're looking to understand a mechanic, you'll want to reference the actual keyword abilities printed on the card's text box.
In Commander, you'd evaluate it like any other creature—on its stats, cost, and printed abilities. If you can tell me the exact card text or which deck it's from, I can break down how it actually plays and where it fits.