Aeglos

You gain a +3 bonus to attack and damage rolls made with this magic weapon.

The first time you attack with the spear on each of your turns, you can transfer some or all of the spear's bonus to your Armor Class, instead of using the bonus on any attacks that turn. For example, you could reduce the bonus to your attack and damage rolls to +1 and gain a +2 bonus to AC. The adjusted bonuses remain in effect until the start of your next turn, although you must hold the spear to gain a bonus to AC from it.

This magic weapon also warns you of danger. While the weapon is on your person, you have advantage on initiative rolls. In addition, you and any of your companions within 30 feet of you can’t be surprised, except when incapacitated by something other than nonmagical sleep. The weapon magically awakens you and your companions within range if any of you are sleeping naturally when combat begins.

In addition, when you hit with an attack using this magic weapon, the target takes an extra 2d6 cold damage. In addition, while you hold the spear, you have resistance to fire damage.

In freezing temperatures, the blade and haft of the weapon shed bright light in a 15-foot radius and dim light for an additional 30 feet.

When you draw this weapon, you can extinguish all nonmagical flames within 30 feet of you. This property can be used no more than once per hour.

 This magic weapon also affords you the ability to cast the spells; Snilloc's Snowball Swarm, Sleet Storm, Ice Storm, Wall of Ice, and Cone of Cold at their native spell levels.

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, Damage: Cold, Advantage: Initiative, Level 10 or above character with at least 3 Fighter levels, 3 Wizard levels and the War Caster and Polearm Master feats, Damage, Detection, Combat, Thrown, Versatile, Sap