You create a bonfire of invisible flames on the ground that you can see within range. Until the spell ends, invisible flames fill a 5-foot cube. Any creature in the space when you cast the spell must succeed on a Dexterity saving throw or take 1d10 fire damage. A creature must also make the saving throw when it moves into the fire's space for the first time on a turn or ends its turn there. Creatures that cannot sense the flames (such as via a special sense or the see invisibility spell) have disadvantage on the saving throw.  

You conjure a globule of glowing molten rock in your hand and hurl it at a target within range, briefly covering them in boiling stone.    Make a ranged spell attack against the target. On a hit, the target takes 4d4 fire damage immediately. The fire damage will occur again at the end of the target’s next turn, but with one less d4 of fire damage rolled. The damage continues to occur and diminishes at the end of the target’s turn by 1d4 until the dice drops to 0d4, then it deals no more damage. On a miss, the arrow splashes the target with lava for half as much of the initial damage, and the spell ends with no further effects.   If the target of the spell takes any cold damage or submerges themself underwater, the molten stone cools into ordinary rock and the spell ends.

You release a blast of flame behind you that rockets you into the air. You fly up to 60 feet in a straight line, stopping at the first creature you contact. You can then choose to make a melee spell attack against that creature, slamming it with a magic barrier. On a hit, the target takes 3d6 fire damage and 2d6 force damage, and it must succeed on a Strength saving throw or be knocked prone. On a miss, the target takes half damage and isn't knocked prone. For this turn, your barrier grants you resistance to damage from falls, and falls do not knock you prone upon landing, but upon finishing the movement and attack caused by this spell, you fall if you are still aloft, unless you can stop the fall.

You conjure a pair of fists made of molten rock, which hover in your space for the duration.   As an action whilst this spell is active, you can make up to two attacks, one for each fist, against a creature within 5 feet of you. Make a melee spell attack for each fist. On a hit, the creature takes 3d6 fire damage. Alternatively, on a hit you can grapple the creature, provided the creature isn't more than one size larger than you. A grappled creature takes 1d6 fire damage at the start of each of its turns. You can grapple one creature per fist. A fist that has a creature grappled can only attack that creature. The DC to escape this grapple is equal to your spell save DC.

A wave of magma and volcanic gases briefly swirl in a 50-foot cube emanating from you that spreads around corners. Each creature in the area must make a Consitution saving throw. On a failed saving throw, that creature takes 1d10 bludgeoning damage, 3d10 fire damage, is knocked prone, and is poisoned for 1 minute. On a successful save, it takes half as much damage and isn't knocked prone or poisoned.

Molten geysers erupt out from the earth in a 40 foot cube centered on a point on the ground that you can see within range. The area extends into the ground and spreads around corners. Each creature in the area must make a Dexterity saving throw, taking 6d6 fire damage on a failed save or half as much damage on a success. Cracks and fissures filled with molten lava open up in the area and churn the remaining solid earth, making the ground in the area difficult terrain until the spell ends. Any creature that enters the spell's area for the first time on a turn or ends its tum there must make a Dexterity saving throw. A creature takes 6d6 fire damage on a failed save, or half as much on a success.    A creature has disadvantage on the saving throw if it is burrowing or prone, but creatures that aren't touching the ground automatically succeed on the saving throw.   This spell ignites flammable objects in the area that aren't being worn or carried When the spell ends, the ground in the area cools, solidifying into difficult terrain until cleared. Each 5-foot-square portion of ground in the area requires at least 10 minutes to clear using mason's tools or a miner's pick.

You create a wall of lava on a solid surface within range. You can make the wall up to 100 feet long and 30 feet high, or a ringed wall up to 50 feet in diameter and 30 feet high. The wall is 3 feet thick. It is opaque, sheds dim light for 30 feet, and lasts for the duration. When the wall appears, each creature within its area must make a Dexterity saving throw.   On a failed saving throw, a creature takes 8d8 fire damage and is restrain- ed by the wall. On a success, it takes half damage and it is pushed out of the wall's space.   Any creature that ends its turn within 5 feet of the wall takes 4d8 fire damage. Creatures can enter and move through the wall, but they must spend 6 feet of movement for every 1 foot moved through it. A creature that enters the wall's space for the first time on a turn or ends its turn there takes 8d8 fire damage and must succeed on a Strength saving throw or be restrained by the wall.   A restrained creature can use its action to make a Strength check against your spell save DC. On a success, it frees itself. This spell ignites flammable objects in the area that aren't being worn or carried.   Obsidian: Spells and effects that deal more than 20 cold damage and pass through the wall cause the wall to freeze into solid obsidian glass where the spell passed through it (at least a 5-foot square section is frozen). Each 5-foot-square obsidian section has AC 12 and 30 hit points and is vulnerable to thunder damage. Reducing an obsidian section to 0 hit points destroys it. When a section is destroyed, the wall's lava doesn't fill it.   If you maintain your concentration on this spell for its entire duration, the wall hardens permanently into obsidian glass instead of vanishing, and it can't be dispelled. Without the spell's magic to maintain them, the destruction of the panels might now cause other connected panels to collapse at the DM's discretion.

There are two possible uses for the spell, granting either immediate or long-term effects.   Lava: If you cast this spell using 1 action, the ground within 60 feet of a point that you choose within range is transformed into superheated molten lava that extends 5 feet deep until the spell ends. The lava sheds bright light for 30 feet and dim light for an additional 30 feet beyond that. A creature walking on the lava must spend 4 feet of movement for every 1 foot it moves. Each creature that touches the lava for the first time on a turn must make a Dexterity saving throw, unless it is already restrained by the lava. On a failed save, it takes 8d8 fire damage and is restrained by the lava. On a success, it takes half damage and it isn't restrained.   Each creature that starts its turn within 15 feet of the lava or enters that area for the first time on a turn takes 4d8 fire damage, or 12d8 fire damage if it is restrained by the lava. When a restrained creature ends its turn, it sinks into the lava. In addition, whenever a creature falls prone within the lava or ends its turn while prone within the lava, it takes 8d8 additional fire damage and sinks into the lava. This spell treats creatures that cannot be prone as if they are always prone instead.   A restrained creature can use an action to attempt to escape. It makes a Strength check against your spell save DC, with disadvantage if it has sunk into the lava. On a success, it frees itself and stands atop the lava.   The lava damages objects in the area and ignites flammable objects that aren’t being worn or carried, and it flows downhill and through holes or channels (at the DM's discretion). When the spell ends, the lava cools and hardens into black obsidian glass. The obsidian is broken wherever a creature would be trapped inside.   Magma: If you cast this spell over 1 hour, you call forth magma deep beneath the land. The spell's material components are consumed, the ground level rises by twenty feet, and if there is a volcano at your location, it grows taller and stronger. Doing this at the same location once every 30 days for 10 years creates a permanent volcano, topped with a permanent caldera that functions the same as the Lava version of this spell. The volcano has a radius of at least 1 mile at its base. It's activity level, topography, and growth rate are determined by the DM.

Your body transforms entirely into magical lava for the duration, granting you the following benefits:

• You are immune to fire damage and you have resistance to all damage except cold damage.
• You ignore the effects of disease, exhaustion, and poisons. Any poisons or diseases already in your system are suspended, not neutralized.
• When a creature ends its turn while grappling you or being grappled by you, it takes 8d8 fire damage.
• You can use an action to try to grapple a creature with a free hand made of magic lava. Make a melee spell attack against one creature. On a hit, the target takes 8d8 fire damage and it is grappled by you and restrained while it is grappled. The grapple's escape DC is equal to your spell save DC.
• When another spell you cast deals fire damage, it ignores resistance to fire damage, and it deals extra fire damage equal to 10 + twice the spell's level. A spell can't deal this extra damage to any creature more than once per turn.