How did the Drifblim outspeed me here?

Question

In this replay, the Drifblim outsped my Tentacruel which it was not supposed to it didn't have a priority move (at least I think), nor was trick room up. I was and am really confused on how it outsped it. Showdown said itself that it had the highest possible speed stat of 185. My Tentacruel in the other hand had 211 speed I thought it was gg for the Drifblim but it outsped and ko'd me.

Here's the replay - https://replay.pokemonshowdown.com/gen8randombattle-1473569465

Answer 1

The Drifblim had Unburden.

Unburden (ability)
Effect
Raises Speed if a held item is used

Knocking off an item registers as the item being "used," which is why Drifblim outsped after Tentacruel's Knock Off. Unburden page for reference.

Hope I helped :)

Comments

Ah i see doing more of this compettetive is making me know more about what ability's and held items do that i don't already know.