What it does
Drill Run is a Ground-type physical move, and like Crabhammer it has a raised critical-hit ratio — it crits more often than a normal move.
Ground coverage is excellent: it hits Steel, Fire, Electric, Poison, and Rock for double. Several of those are walls other types can't crack, Steel most of all — plenty of moves get stonewalled by Steel, and a Ground move just doubles through it. That's why Drill Run shows up as a coverage move on non-Ground Pokémon, plugging the holes their main type can't reach.
The crit angle matters because it ignores the target's defense boosts. Against something that's stacked Defense or set up, a normal move bounces off, and a Drill Run crit goes straight around it.
Who runs it
Lycanroc runs Drill Run in Champions at 8% usage — a niche pick, mostly as coverage. Lycanroc is Rock, and Rock STAB doesn't double against Steel or Fighting (Fighting even resists it), so Drill Run adds the doubled hit on Steel that it otherwise lacks. Whether you slot it depends on who you most need to cover: if Steel threats are common in your meta, this move earns its spot.
How to use it
Drill Run is single-target, so in doubles it never splits and hits one foe for full. Its job is the targets Lycanroc's Rock can't dent — Steel especially. If a Steel sits in front and walls your Rock damage, click Drill Run to double it down.
In doubles, pick the target carefully — Drill Run hits one foe, not both like a spread move. Each turn, judge which hit is worth more, and lean toward the foe that takes double from Ground and threatens your partner.
The high crit rate shines against bulky walls. If the foe is surviving on defense boosts, a Drill Run crit ignores those boosts and is your ready-made way through.
Tips & strategy
Ground moves miss Flying types entirely, and they miss anything with Levitate — both are fully immune. So check the foe's typing before you click: a Drill Run into a Flying or Levitate target does nothing.
A high crit rate only bumps the odds up one stage; it's not a guaranteed crit. Don't pencil a crit into your kill math, or the no-crit turns will leave the foe alive.
Drill Run isn't perfectly accurate, so respect the miss on a key cleanup turn. If you've got one shot at the KO and a whiff scares you, a more accurate move is the safer call.