Bonus Cantrip: Druids have fewer cantrips than any other casting class, so this evens the playing field.
Natural Recovery: This ability is incredible. Spells are the most powerful metric in the game, and you have a renewable supply of them.
Circle Spells: This is the main feature of this Druidic Circle. You gain additional spells prepared based on which biome you choose.
Arctic: This circle gives you a few crowd-control options, but most of them are concentration spells.
3rd Level: Hold Person and Spike Growth are two of the best control options available at low levels.
5th Level: Spike Growth is better than Sleet Storm. Slow is solid, but still requires concentration.
7th Level: Freedom of movement is wasted on a shapeshifter. Ice Storm is a powerful area control spell.
9th Level: Cone of Cold is incredibly strong, and dips into a rare damage type for Druids. Commune with Nature is a middling divination spell.
Coast: This circle starts very promising, but tails off quickly. Great for someone cross-classing into it.
3rd Level: Mirror Image and Misty Step almost totally ensure you won’t get tagged in melee.
5th Level: Two very situational spells you don’t need once you can Wild Shape into a swimming creature.
7th Level: Two more situational spells you won’t use.
9th Level: Scrying is somewhat useful, but Conjure Elemental is the real star here.
Desert: This circle gives you a weird collection of spells not normally available to Druids.
3rd Level: Blur is a great defensive spell. Silence is amazing. It’s the prefect stealth spell, and can completely shut down an enemy spellcaster.
5th Level: Create Food and Water isn’t terribly useful unless you’re playing a game where wilderness and travel survival are very important. Protection from Energy is one of the best “About to fight a dragon” preparations you can make.
7th Level: Blight is situational, but when it comes up it’s just plain mean. Hallucinatory terrain is tough to find a use for, but when you need it, it’s great.
9th Level: Two amazing crowd control options.
Forest: This circle is lackluster, and low on the power level of the spells it provides.
3rd Level: Barkskin is a solid defense option. Spider Climb is situational, since you can turn into a giant spider.
5th Level: Call lightning is one of the most efficient spells available to Druids. The problem is that it’s already available to Druids, so getting it from the Circle is redundant. Plant Growth is situational.
7th Level: Two very situational options you may never use.
9th Level: Tree Stride is neat but getting regular Teleport would be a lot better.
Grassland: This circle is all about the buffs.
3rd Level: Both of these spells are incredible for infiltration and recon. One for just you, and the other for the whole group.
5th Level: Haste is the single best buff in the game.
7th Level: Two mediocre situational spells.
9th Level: Insect Plague is an excellent area control spell.
Mountain: A strong contender for the best circle, this provides good options all the way through.
3rd Level: Spider Climb is redundant when you can turn into a spider. Spike Grown is very powerful at low levels, and continues to produce even later on.
5th Level: Lightning bolt is a powerful weapon for Druids.
7th Level: Stone Shape and Stone Skin are both very powerful spells
9th Level: Make a wall, pass through the wall, your choice.
Swamp: Another circle that has great options at low levels, and tapers off quickly.
3rd Level: Two good non-Druid spells.
5th Level: Stinking Cloud is fantastic area control.
7th Level: Both spells at this level are very situational.
9th Level: Insect Plague is excellent area control.
Underdark: Almost all of these spells are not normally available to Druids.
3rd Level: Spider climb is bad for you, but Web is oh so very good.
5th Level: Stinking Cloud is good area control, and Gaseous Form is a great infiltration and escape option.
7th Level: Greater Invisibility is second only to Haste as far as buffs go, and Stone Shape is a very useful tool to have in your arsenal.
9th Level: Cloudkill is powerful. Insect Plague is excellent area control.
Land’s Stride: This is a very situational ability, but if you choose right, you’ll enjoy having it.
Nature’s Ward: Again, situational, but more useful than the others.
Nature’s Sanctuary: Never fear, if you encounter a Beast or Plant foe you’ll have a great chance of avoiding the combat encounter or settling it quickly.