Arcane Ammunition

Anyone can improve or cast a boring old magic missile, Jim. Sure, your version deals more damage, especially on critical hits. Yawn. Do away with Jim's Magic Missile and try out this more advanced version of the spell, invented by me Lorde Providence the greatest Artificer in the land hahaha. 

As a bonus action, you can touch four nonmagical items (ideally a gold coin or blunderbuss bullet) and infuse them with magic. On your next available turn as an action, you can make a ranged spell attack of 120 feet for each ammunition. The ammunition is launched simultaneously, and you can direct them to hit one creature or several. On a hit, an ammunition deals 1d6 + your spell modifier of force damage.

If the attack roll scores a critical hit, the ammunition explodes on impact. The target and each creature within a 5 feet radius must succeed on a Strength saving throw or take 1d8 + your spell modifier of force damage and is pushed 15 feet from the blast radius. On a successful save, a creature takes half as much damage and is only pushed 5 feet. If the attack roll is a 3 or lower, all ammunition become unstable and miss their targets, flying frantically around hitting any other target within range. All other creatures within range must make a dexterity saving throw or be hit with 1d4 force damage per ammunition. Hit or miss, the spell infusion ends with that nonmagical item.

At Higher Levels. When you cast this spell using a spell slot of 2nd level or higher, you can infuse additional nonmagical items and the infusion component increases by 1 Gb, for each slot level above 1st. At a cost, when you cast this spell using a 5 level spell slot or higher, you can infuse more magical energy into the items causing your critical miss to increase to 4 and your critical hit to also knock the targets prone. Each creature must succeed a Strength saving throw. On a successful save, all creatures aren’t knocked prone. After the spell ends, you can’t cast spells other than cantrips until the end of your next turn. When you cast this spell using a 9th level spell, the damage increase to a 1d8 and the ammunition all strikes simultaneously towards one creature. No attack roll is required but immediately after the spell ends, you must succeed on a DC 18 Constitution saving throw or suffer one level of exhaustion.