With the SV metagame coming out soon, looking to be pretty offensive with many new threats and PP of recovery moves outside of Strength Sap being cut in half. May I suggest to defensive teams one Pokemon they can use.
Maushold.
Ok, but why Maushold? It's frail.
Well Defensive teams in the past have often employed frailer Pokemon like Dugtrio as an infamous example, but also Pokemon like Starmie, Weavile, and Zeraora have found huge success on defensive teams in past generations for their ability to handle offensive teams and wallbreakers. Their blazing speed and ability to threaten most offensive Pokemon allowed the defensive cores of a team to be at ease with such offensive pressure.
With Maushold, you have a pretty fast 111 Spe Pokemon. This is actually normally slower than usual offense on defense Pokemon. However, Maushold has a great toolkit for helping against offense.
-Tidy Up, a new move exclusive to Maushold, is basically a Dragon Dance+Defog (without evasion drop, which is also important)
-Population Bomb, a normal move that is like Triple Axel, but effectively 200 BP normally and hits 10 times
-Bite/Beat Up and Low Sweep
-Technician
Tidy Up and Population Bomb are the 2 key components, while Bite/Beat Up and Low Sweep are mostly there as coverage for offensive threats like Houndstone and Kingsgambit.
Tidy Up is absolutely excellent for Maushold being on a defensive team as it makes Maushold a premier hazard remover. Being able to remove hazards without procing Defiant and while also being a massive threat to most of the frailer offensive teams. Population Bomb more than makes up for its 75 Atk. It's already pretty strong against several defensive Pokemon and OHKOs a lot of neutral targets after a +1 Atk. Normally when defensive Defoggers try removing Hazards, they often let something safely switch in, and for Maushold, nothing on Offense really safely switches in due to it being insanely fast and being able to remove anything that isn't a ghost/steel/rock type instantly. Also, unlike Defog, any hazard setter on the opposing team can't just spam Stealth Rock or Spikes because doing so only makes Maushold stronger.
So I hope this may be good advice for people when making defensive teams. This gen will be pretty wild.