You use your earthern jutsu to turn the ground into fine sand and you use your chakra to dig through the ground where you can sense everything, you can't perform handseals and can only perform C rank and below Earth jutsus, doesn't leave a trace. And, an advice, you don’t want your opponent seeing you use this, Swamp of underworld will kill you.
(Doton: Moguragakure no Jutsu) – Earth Release: Hiding like a mole technique
Rank: C
Type: Supplementary
Range: Long
Chakra cost: 15
Damage points: N/A
Description: The user changes earth into fine sand by channeling chakra into it, allowing the user to dig through it like a mole. While underground one can sense what is happening on the surface and use the information to launch a surprise attack on the enemy. Once can also hide deep in the ground, escaping to a depth where the enemy cant reach. It also appears that after digging, the ground can be returned to its original state, leaving no trace of where the user entered the earth. While inside the earth, the user cannot make handseals and can only use Earth techniques below C-Rank. If he tries to do a higher ranked technique, he'll disrupt the Hiding like a mole technique and be left crushed.
You create spikes from the ground to hit a target. Easy.. It pierces less dense objects, can be created from any earrh source. Ofc, you can't create the spikes from enemy's jutsu of higher rank
(Doton: Ganchūsō) - Earth Release: Stone Spikes
Rank: C
Type: Attack
Range: Short-Mid
Chakra Cost: 15
Damage Points: 30
Description: This technique lets the user create a few rock pillars that will protrude from the ground to skew the target. The rock pillars will even pass through obstacles to reach their target if these are less dense. The pillars/spikes can be done in any earthen surface, including other earth techniques of the user.