Cavern God Slayer Magic

Cavern God Slayer Magic (洞窟の神スレイヤーマジック Dōkutsu no kami sureiyāmajikku) is a type of Caster Magic, Lost Magic, Slayer Magic, and a type of God Slayer Magic that involves the control of the Earth. Unlike most other earth-type god slayer magics, Cavern God Slayer Magic can only be used if there is sufficient ground around the user. As in, a user cannot produce the element out of their own body, but can only use the surrounding terrain to fight. This effectively makes it useless on the ocean, in the air, or other areas where there is not sufficient rock material.

Description
As stated above, Cavern God Slayer Magic is a unique type of Earth God Slayer Magic that involves the element of earth. The difference between this type and earth-type god slayer magic is that Cavern God Slayer Magic does not allow the user to produce earth from their own body. Instead, the user must constantly eat the surrounding earth to build charge for their spells, before expending it like a battery.

Obviously, this type of magic is almost completely useless on large bodies of water, or while in the air. So, the user must be very careful to stay on the ground while fighting or his magic will be nullified. However, despite the impressive drawbacks, this type of God Slayer magic is very potent and can generate devastating earthquakes, and it allows the user to have full control over the terrain in a 300 ft radius around them.

Spells
Cavern God's Bellow (洞窟神のベロー Dōkutsu-shin no berō): The user must first consume some amount of earth before this spell may be cast, of course, the power of this spell comes from how much of the earth is eaten, as well as the fertility of the earth they have consumed as well. Then, the user can release it much in the same way other God Slayer Bellows are released, in this case in the form of a powerful jet of mud, rock, and other dense material to cause lethal blunt trauma.

Cavern God's Erupting Ground Fist (洞窟神の噴出グラウンド拳 Dōkutsu-shin no funshutsu guraundo ken): Similar in matter to the Earth God's Rock Bursting Fist, this spell is the second most basic spell in a user's arsenal and it is mainly used for close combat. The user has to consume a substantial amount of earth to be able to use this spell effectively, and then the user can extend their arm forward (usually towards their target) before a large fist erupts from the ground beneath the opponent, this fist can be large or small depending on the user's wishes, and how much earth they consumed beforehand.