Sapper

The archetypal sapper is intimately connected with the earth. Having spent countless hours toiling underground, the sapper is an expert in using their knowledge of soil and digging against their enemies. They can turn the earth into a powerful weapon for both defense and offense, bolstering their allies and striking down their foes.

Natural Excavator

Beginning when you choose this archetype at 3rd level, you gain a burrowing speed of 30 feet and a tremorsense with a range of 10 feet. Any attack you make from underground has neither advantage nor disadvantage.

Canary in a Coal Mine

You have become more alert to potential threats from your time in confined spaces underground.

At 7th level, you can add your Constitution modifier to your initiative rolls.

Your alertness has also allowed you to shore up your party's defenses when resting. During a short or long rest, you can build improvised fortifications in a 15-foot radius from earth and stone around you and your allies. These fortifications provide total cover against ground attacks and half-cover against aerial attacks. You also learn the Alarm spell, which you can cast once per long rest as a part of the fortifications you construct. Constitution is your spellcasting modifier for this spell.

Antlion's Strike

You now excel at attacking enemies from below.

Starting at 10th level, when making a melee weapon attack against an enemy after using your burrowing speed to reach directly underneath them, you can explode out in a burst of soil, dealing an additional 2d8 bludgeoning damage. This increases to 4d8 bludgeoning damage when you reach 15th level. You can use this feature a number of times equal to your Constitution modifier, and you regain all uses on a long rest.

Dig In

Starting at 15th level, you excel at defending yourself against attacks by digging your heels in and standing your ground against any attackers. When you use no movement on a turn, you gain a +4 bonus to your AC until the beginning of your next turn.

Cave Collapse

You can now tunnel underneath your opponents and wreak tremendous havoc against them.

Starting at 18th level, you can burrow rapidly beneath your enemies a distance equal to twice your movement speed in a straight line. All creatures standing above your tunnel in a line must make a Dexterity saving throw with a DC equal to 8+your proficiency bonus+your Constitution modifier. On a failure, they take 8d12 bludgeoning damage. On a success, they take half damage. You can use this feature once per long rest.