Aeglos, the Crimson Spear

Created by the tiefling Roth for his son Glorfindel, Aeglos is a marvel of gleamtech engineering with an artifact from the Crimson Wastes used as its core. When unattuned, this spear appears as a crimson gauntlet. Upon donning the gauntlet, if this was done by Glorfindel, Aeglos attunes immediately and its true form can be revealed.

You have a +1 bonus to attack and damage rolls made with this magic weapon, and you may use your Intelligence modifier instead of Strength or Dexterity when attacking. Aeglos may be used as a spellcasting focus for your artificer spells. You may add an Artificer Infusion to Aeglos without it counting against your total number of infused items. If an infusion added to Aeglos gives a bonus to damage or attack rolls, it does not give this bonus; the other effects remain unchanged. 

As a bonus action, Aeglos can change forms. When in gauntlet form, Aeglos's true form is indiscernible.

Aeglos gains bonus effects in both Guardian and Infiltrator forms:

Guardian

When attacking with the thunder gauntlets, you may choose to deal radiant damage instead of thunder and gain +1 to the attack and damage rolls.

If a creature given disadvantage by the gauntlets lands their attack, you gain advantage on your next attack against them until the end of your next turn.

If you are at or below 25% of your hitpoint maximum (rounded down) when using Defensive Field, double the amount of temporary hitpoints gained.

Infiltrator

Your lightning launcher's normal range extends to 120 feet and its damage type changes to radiant.

You may cast Mirror Image once per day without using a spell slot.

 

Last Resort

When casting a spell using Aeglos as the spellcasting focus, you may add 3 to the level of the spell slot being used. When a spell is cast in this way, you take damage equal to the final level of the spell, gain a point of exhaustion, and Aeglos loses all other special properties and bonuses and functions as a normal spear until the next dawn. It may still shift between its gauntlet and spear form. If the spell that is cast has a duration, the negative effects are delayed until the spell ends.

Proficiency with a Spear allows you to add your proficiency bonus to the attack roll for any attack you make with it.

Notes: Bonus: Magic, Replace Damage Type: Radiant, Bonus: Magic Item Attack With Intelligence, Bonus: Magic Item Attack With Intelligence, tiefling named Glorfindel, Damage, Combat, Thrown, Versatile, Sap