Dig

For the duration, you gain the ability to Burrow through nonmagical earth, sand, and mud at half your Speed, and leave a 5 foot-wide, 5-foot-high tunnel in your wake. Alternatively, you can burrow through unworked stone, such as natural cavern walls, with a Burrow Speed of 5 ft., but you can't move across stone floors and walls built by intelligent creatures.

When the spell ends, the tunnel collapses 10 minutes later. The material thrown from the excavation magically scatters evenly outside the tunnel, creating a 5-foot radius of Difficult Terrain for every 10 feet of excavated terrain. 

A creature caught in the collapsing tunnel must make a Dexterity saving throw. It has Advantage on the saving throw if it is within 5 feet of an exit. On a failed save, the creature takes 3d6 Bludgeoning damage, or 5d6 if burrowing through solid rock. It is also knocked Prone, and is Buried.

You can flavor your ability to burrow as growing umber hulk-like claws. Your Unarmed Strikes with these claws deal 1d6 Slashing damage instead of dealing the normal damage for your Unarmed Strike, and you use your spellcasting ability modifier for the attack and damage rolls rather than using Strength.

Using a Higher-Level Spell Slot. The duration of the tunnel before it collapses increases: 1 hour for a 5th level slot, 8 hours for a 6th level slot, 24 hours for a 7th level slot, 7 days for a 8th level slot, permanent until dispelled for a 9th level slot.

BURIED

While you are Buried, you experience the following effects.
Sight and Mobility Affected. You have the Blinded, Prone, and Restrained conditions.
Possible Suffocation. You must make a DC 13 Constitution saving throw. On a successful save, you have a lungful of air and can hold your breath for a number of minutes equal to 1 + your Constitution modifier (minimum 30 seconds) before suffocation begins. When you run out of breath, you gain 1 Exhaustion level at the end of each of your turns. If you reach 6 Exhaustion levels, you fall to 0 Hit Points and start making Death Saving Throws (instead of dying outright).
Escape. As an action, you can make a Strength (Athletics) check to attempt to escape. A creature that isn't Buried can also use their action to make the check or assist you with the Help action. The DC equals 15 or the DC of the spell or effect that caused the condition. If you are freed and can breathe again, you remove all levels of Exhaustion you gained from suffocating, unless a spell or effect tells you otherwise. 

Adapted from the 1st edition (AD&D) spell