Booming Blade

Overall Rating: Black. This means that booming blade has vastly different ratings based on how you plan on using it.

Overall Notes: Most casters will want to avoid this unless they are up in the mix as a martial spellcaster. This can be a great tool to lock enemies down if you're being pursued or would like to move around the battlefield to get an advantageous position. Unfortunately, shoving or other methods of knocking prone doesn't activate the extra 1d8 damage. This spell works particularly well with the Mobile feat as you can attack then move without giving your opponent an attack of opportunity. In practice, it works extremely well with the Polearm Master and Sentinel feat combo, but you will need to pick up a way to extend the range of your cantrip, either by using the Spell Sniper feat or the sorcerer's Distant Spell Metamagic. Finally, this spell works wonders with War Caster as you can hit an enemy booming blade as an opportunity attack and prevent your opponent from running away.

Class Specific Ratings for Booming Blade

Eldritch Knight fighter: Another great cantrip + bonus attack option for when you pick up War Magic at 7th level.

Arcane Trickster rogue: This cantrip is really nice because Rogues can Disengage as a bonus action. You can attack and run away, forcing your foe to take damage if they want to pursue you. It also triggers Sneak Attack, which makes it optimal to use in most circumstances.