Tempest Bolt

You produce a bolt of brilliant blue lightening (or colour of your preference) that strikes a a creature within range. Make a ranged spell attack against the target. If the bolt hits the target, it takes 1d8 lightening damage If the target is wearing plate armour made of metal that is nonmagical, the attack has advantage. 

At Higher Levels. This spell's damage increases by 1d8 when you reach 5th level (2d8), 10th level (3d8), and 15th level (4d8). 

Spell lists. Sorceror, Artificer, Wizard, and Bard.

Author's Note; Might be a glitch on my end, by the character sheet function won't display the higher level damage in the spells column where it details the spell's damage, it being stuck at 1d8. I can't exactly find the issue between how I made this spell function and a Fire Bolt spell as for the higher leveling, so for now it's something to just keep track of mentally as you level. Edit- The feature is working properly just like any spell now, so there are no issues! I'm only keeping the note here to keep track of issues I experience in homebrew, and if anyone views my content before issues are fixed then the edits show the fix occurred.