The 2020 rotation and the arrival of the new Standard Year will, as always, be decisive in Hearthstone.
Three expansions will rotate out of Standard mode (Witchwood, Boomsday Project and Rastakhan's Rumble) and this should create a real revolution.
While they'll still be able for playing in Wild mode, a lot of Warrior cards from the previous expansions are going to leave the Standard mode, meaning that several different archetypes that are currently shaping the meta will be affected — or will even disappear.
Some of these cards weren't really used, but the disappearance from some others will definitely be noticed...
Witchwood
The Boomsday Project
Rastakhan's Rumble
Since Baku was sent to the Hall of Fame, the Odd Warrior disappeared after the 2019 rotation — it hasn't been played at all since. Only the Dr. Boom version of the Control Warrior has been really popular and has made the Open Cup infinitely long with the help of Elysiana.
And precisely, the loss of all this "Mechs+ Boom package" should be a very heavy blow to the archetype. The Galakrond Warrior will hardly see the difference, just like the Pirate Warrior which had been retested a few weeks ago by a few players. Whether the next expansion will bring enough good cards to support a Control archetype is another question...