More fever dreams and mixing with my day job reading about biochemistry.  Why no necromancy fireball?  I GOT YA NECROMANCY FIREBALL!

Buboes Explosion

3rd-level necromancy

Casting Time: 1 action
Range: 100 feet
Components: V, S, M (a lymph node cut from a plague victim)
Duration: Concentration, up to one minute

You fling the dried lymph glad to a point in range and it explodes in a black mass of smoke.  Each creature in a 20-foot-radius sphere centered on that point must make a Constitution saving throw. A target instantly becomes infected with a pox if it fails the save becoming covered with boils and pustules.  Any creatures who make their save are unaffected.  Each turn an affected creature takes 3d6 necrotic damage at the start of its turn while affected.  Any ability that removes diseases ends the effect on an affected creature.  Creatures immune to disease are immune to this spell.

At Higher Levels: When you cast this spell using a spell slot of 4th level or higher, the damage increases by 1d6 for each slot level above 3rd.

Thoughts?

I’ve been pretty sick this weekend.  CANCEL DND SICK!  But it does give me some ideas….

Wracking Cough

1st-level necromancy

Casting Time: 1 action
Range: 30 feet
Components: V, S
Duration: 1 hour

You attempt to hamper a target in range with a debilitating cough.  Choose a target in range.  If it fails a Constitution saving throw,  it gains a debilitating cough.  Each round if it attempts to do more than just stay still and rest, it must make a Constitution saving throw.  On a failure it gains disadvantage to all attacks and skill checks for that round as well as saves made before the beginning of its next turn.   Any effect that removes a disease or magically heals damage removes this cough.

At Higher Levels: When you cast this spell using a spell slot of 2nd level or higher, you can target one additional creature for each slot level above 1st. The creatures must be within 30 feet of each other when you target them.

How about a low level druid boost spell?

Bestial Fury

1st-level enchantment

Casting Time: 1 action
Range: Touch
Components: V, S, M (claws and teeth of a badger)
Duration: Concentration, up to 1 minute

This spell throws a target into a fury.  When you touch  a creature, that creature may attempt a Wisdom saving throw.  On a failure, that creature loses all spell casting abilities and any abilities that require mental concentration and instead gains the rage of a creature of your level or CR.  The rage lasts for as long as you concentrate on the spell.

At Higher Levels: When you cast this spell using a spell slot of 2nd level or higher, the number of affected creates increases by 1 for each slot level above 1st.

Thoughts?

Todays spell for the wizard!

Eurytus’ bow

1st-level conjuration

Casting Time: bonus action
Range: Self
Components: V, S, M (a shard of pottery)
Duration: 1 minute

This spell creates a floating wooden bow or crossbow that moves with you and stays within 5 feet of you.  The bow operates as normal, requiring an action to use, but the bow will conjure an arrow as part of the action to fire the weapon.  The action that fires the weapon does not require you to use your hands, and you use your spellcasting attack modifier for the attack.  The weapon does damage as a non-magic bow.  The bow can be attack as normal and for all purposes is a normal wooden bow for targeting, hit points, AC, and damage.

Thoughts?