Comments from the Finger: You know, this is the closest thing we'll get to a magitech druid for a while.
Circle of Steel
Most druids consider metals to be the domain of civilized races and an emblem of civilization's exploitation of nature. For this very reason, many druids refuse to wear metal armor or wield weapons composed of iron or steel.
But the Circle of Steel thinks differently. Metals, like all things, come from the earth, and have as much a natural place in the world as any other material. These druids most highly praise the Ironwood Tree, which is a living amalgamation of metal and wood, which to them stands as a symbol of how to use metals in perfect balance with nature.
When you choose this circle at 2nd level, you can wear metal armor and shields and you gain proficiency with martial weapons.
At 3rd level, whenever use your Wild Shape while armored, your metal weapons and armor become merged with the beast, transforming into a living conglomeration of animal and steel. You can use your armor class in place of the beast's, if it is higher. If you are holding a metal melee weapon when you transform, you can also use your weapon's damage die in place of the beast form's melee weapon attack damage dice, if it is higher.
At 6th level, your attacks in beast form count as magical for the purpose of overcoming resistance and immunity to nonmagical attacks and damage.
By 6th level, your connection with the metal of the land grants you a new magnetic sense. You always know which direction is north and have advantage on Wisdom (Survival) checks made to navigate.
You can also use your action to detect the presence of nearby metal objects around you. To do so, make a Wisdom check with a save DC of 10 + 1 for each 100 feet you choose to sense. On a success, you can detect the largest metal object within range, and the precise direction to it. If you beat the DC by 5 or more, you can detect the number of metal objects within range and the direction to each. If you beat the DC by 10 or more, you can detect very small objects, like coins or nails, within range, and the direction to each.
Starting at 10th level, as a reaction when you take nonmagical bludgeoning, piercing, or slashing damage, you can reduce the damage inflicted by 1d10.
At 14th level, you can attract magnetic ore from the earth and cause it to rise beneath your enemies. As an action, select a 15 foot square area on the ground. Nonmagical metal walls rises up from the earth, surrounding the area. The walls are four three-inch thick, 15-foot-by-15-foot panels. If the wall cuts through a creature's space when it appears, the creature is pushed to one side of the wall (your choice.)
The wall is an object made of metal that can be damaged and thus breached. Each panel has AC 16 and 60 hit points. Reducing a panel to 0 hit points destroys it and might cause connected panels to collapse at the DM’s discretion.
This metal ore crumbles into rust after a number of rounds equal to your Wisdom modifier. After using this ability, you must complete a short or long rest before using it again.
Changelog: 8/29/16: Metal Tomb: Should last Wis mod rounds
Steel Beast: Replaces Iron Flesh
8/30/16: Iron Defense: now 1d10