UnderRail: Heavy Duty

This DLC adds three new weapon types - grenade launchers, machine guns and miniguns, as well as a special high-level side mission that will challenge even the most hardcore Underrail veterans.

Key features:

• New skill "Heavy Weapons" which covers two new weapon types - machine guns and miniguns
• Grenade launchers, a area of effect type weapon, added to Guns skill
• New high-level side mission where you'll fight against elite enemies
• New feats

Source:

Steam Store Description