Astral Brand

Speaking a Word of Creation, you brand your target's body and soul with a rune of weakness.  Make a ranged spell attack against one creature you can see within range and choose the rune you wish to brand them with from the list below.  On a hit, the target takes 4d10 damage of the type associated with the rune you chose, and the target gains vulnerability to that damage type for the duration of the spell.  The target also suffers an additional effect based on the rune you chose.  

• Vutha - Acid damage, and the target takes a -2 penalty to AC for the duration of the spell.
• Aussir - Cold damage, and the target's movement speed is reduced by 10 for the duration of the spell.
• Ixen - Fire damage, and the attack deals 6d10 damage rather than 4d10.
• Ulhar - Lightning damage, and the target takes a -2 penalty to saving throws for the duration of the spell.
• Kear - Radiant damage, and the target takes a -2 penalty to attack rolls for the duration of the spell.
• Loex - Necrotic damage, and you regain hit points equal to the necrotic damage dealt.
• Kepesk - Thunder damage, and you push the target 10ft and knock them prone.  

On a miss the target takes half damage and gains vulnerability to the associated damage type until the end of your next turn, but suffers no other effects.  

At Higher Levels: When you cast this spell using a spell slot of 5th or 6th level, you can brand one additional rune onto a target (total of 2).  Make a separate attack and damage roll for each rune.  You may target the same creature or different ones, but you cannot brand the same rune onto the same creature more than once.  When you cast this spell using a spell slot of 7th or 8th level, you can brand a total of 3 runes onto your target (or targets).  You can brand 4 runes when you use a 9th level spell slot.