I didn't think anyone would do a druid before the contest ended, so here's my submission. It's supposed to be a more utility-focused alternative to the Moon Druid. I'm not entirely sure I succeeded with that, but I'd rather it be too weak than too strong.
Circle of Progress
Druids rarely use too many benefits of civilization and technology, preferring rather to rely on the natural world for their power. However, a select handful have decided that, as sapient races are the outcome of natural processes, so too their products must also be natural. By forming a connection to the primal energies underlying forged constructions, these druids can incorporate new technological capabilities when they take on a new form.
Druids of this circle will use metal armor and shields if they desire its protection. Their wielding this protection does not negatively impact their class features.
Starting at 2nd level when you choose this circle, you can incorporate additional abilities when you use your Wild Shape feature, melding your equipment on-hand into special augmentations for your new body. When you use your Wild Shape feature, you can choose to add one of the following benefits to your animal form:
- Climate Control: You have resistance to cold and fire damage.
- Nighteyes: You gain darkvision out to 60 feet and blindsight to 5 feet based on hearing.
- Internal Dampeners: You have resistance to lightning and thunder damage.
- Reinforced Body: You gain proficiency with Constitution saving throws and add 1 to your AC.
- Reinforced Limbs: You gain proficiency with the Athletics skill and Strength saving throws as well as an additional 10 feet to your current walking speed.
Additionally, rather than gaining the natural attacks of your chosen form, you can incorporate one melee weapon into your new form. The weapon deals damage based on your formís size and of the same damage type as the original weapon you transformed. You can use your Strength modifier (or Dexterity modifier, if your chosen form's Dexterity score is higher) with the weapon, adding the ability score to your attack and damage rolls. If your chosen form has Multiattack, you can use this weapon with that feature.
- Tiny animal: 1d4
- Small: 1d6
- Medium: 1d8
- Large: 1d10
These benefits last until you end this use of Wild Shape.
At 6th level, you can incorporate your armor into your Wild Shape feature, transforming it into a form suitable for you and gaining any bonuses it provides to AC. If your chosen form has natural armor, your armor replaces any bonus it provides. Additionally, if you incorporate a magical weapon into your Wild Shape using your Transformed Shape feature, your incorporated weapon counts as magical and you gain any bonus it provides to attack or damage rolls and can use any of its abilities.
Starting at 10th level, when you use your Wild Shape feature, you can gain one of the following abilities in addition to one of those listed under your Transformed Shape feature:
- Adrenal Injection: As a bonus action, you can take the Dash action and, as part of the same bonus action, choose to spend 1 Hit Die to regain health.
- Construct in Disguise: Your type changes to construct instead of beast. You gain immunity to poison and the poisoned condition. A creature can make a Perception check (DC = your druid spell save DC) to notice your artificial nature.
- Reactive Sensors: You gain proficiency with Dexterity saving throws and, when targeted by a melee attack, can use your reaction to impose disadvantage on the attack roll.
- Target Marked: You can use the Help action as a bonus action to assist an allyís attack.
Alternatively when you Wild Shape, you can choose two of the benefits listed under your Transformed Shape feature and gain both.
At 14th level, you gain the ability to project magical aid while using your Wild Shape feature. You can cast blur, heroism or warding bond as a 2nd-level spell once during each use of Wild Shape without requiring material components or using a spell slot. The effects of the spell end if you end your current use of Wild Shape.
Edit: Thanks to PhoenixPhyre have made some minor changes and added the Metal Armor note.