Hey! I’m Tokaine, the best tank you’ve never heard of and the number 1 advocate for T.D.M (Tank Damage Matters). I’ve been tanking since cataclysm, mainly playing protection warrior until legion where I branched out into other tank classes as I climbed the world ranks.
Guardian Druids has for long been known as a meat-shield that has very high HP. This makes druids very good against magic damage as their high health pool allows them to take a couple of extra hits, however they do take quite a fair bit of magic damage.
In Shadowlands, druids have a strong self-heal in Frenzied Regeneration. They also have a good set of cool-downs to use and rotate through. Survival Instincts being the front-runner and the most powerful damage reduction available to the different tank specs. Additionally Ironfur is guardians stackable active mitigation which you can stack up to ridiculous levels during Berserk.
What has changed
In Shadowlands guardian druid got a couple of good changes. This has pushed the spec to be a strong tank in Mythic+ and pretty much the best tank in PvP. Additionally when you utilise cat and owl weaving, you are able to pump out ludicrous tank damage which is really strong during progress when every point of damage matters.
Cyclone, Infected Wounds, Tooth and Claw as well as Berserk were all added to the spec. Blizzard also added a lot of strength to Incarnation: Guardian of Ursoc as it now makes your Frenzied Regeneration cooldown faster, as well as making Ironfur cost only 20 rage during the duration. This together with the legendary Ursoc's Fury Remembered makes guardian a really strong tank in Mythic+.
If you want to play a guardian druid in PVP, the legendary Legacy of the Sleeper makes you immune to CC for the duration of Incarnation, this makes you the best at defending bases as well as flag carrying. If we ever get to equip 2 Shadowlands legendaries at the same time, guardian druids will definitely be considered one of the strongest tanks as they have some really good legendaries that synergize together.