Gun Kelvin Build by Sharky

The first 2 purchases of the lane phase Headshot Booster and High-Velocity Mag increase weapon damage which Kelvin lacks in the early game.

Hollow Point Ward for increased conditional weapon damage and spirit shield.

Next Extra Charge for more Frost Grenade and added weapon damage.

3 important Vitality items Extra Regen, Sprint Boots, and Extra Health increase movement speed, damage, and sustain.

Lastly Mystic Reach for increased ability range and bullet resistance.

First 2 priority purchases Berserker and Bullet Resist Shredder for larger mag size and increased bullest resistance on targets hit with Frost Grenade.

Next Quicksilver Reload imbued onto Frost Grenade (Spirit Armor is optional if the enemy team is scaling fast).

Kinetic Dash for increased fire rate paired with Enduring Speed for movement speed movement slow reduction.

The first purchase of the late game is an upgrade which builds out of Headshot Booster (Headhunter) and Fortitude for bonus health and conditional weapon damage and movement speed.

Pristine Emblem (component of High-Velocity Mag) for spirit resistance, weapon damage and bullet velocity and to top it off Burst Fire for more fire rate and movement speed.

The last 2 items are situational depending on the enemy teams bullet resistance if super tanky Crippling Headshot if not much resist Frenzy.

Rapid Rounds for more Frost Grenade and cooldown reduction + 12% weapon damage increase. 

Return Fire for enemy team with alot of weapon damage.  

The best time to add Improved Bullet Armor and Improved Spirit Armor is situational depending how fast on enemy team scales but is usually purchased during the mid to late game.

Debuff Reducer or Debuff Remover are great options against teams with large amounts of debuffs and stuns, especially against Knockdown and Slowing Hex.