Pewter

Added:

Embers: Rekindled support. It adds two materials:

• Dawnstone (Tools & Armor)
  • Simmer (Tool Trait): Deals increased damage at lower elevations.
  • Dawn (Tool Head) - High knockback and a chance to set mobs on fire, scaling up with lower attack speed.
  • Branded (Armor Trait) - If at very low health, damage is heavily reduced based on toughness. The more toughness you have, the less damage you'll take.
• Ashen Fabric (Armor)
  • Ashwoven (Armor Trait) 15% resistance to fire damage, 10% weakness to other forms of attack

Soot (Embers addon) support. It adds one material:

• Antimony (Tools & Armor)
  
  • Quenching (Tool Trait) - Hitting enemies on fire will put them out, dealing scalding damage.
  • Squelching (Armor Trait) - Upon damage, if on fire, has a chance of reducing it's duration.

For modders & modpack makers:

You can make some very basic custom materials for Tinkers' Construct with Pewter. You can look at how to do that here.

There's now an API for Pewter as well, written in Kotlin. This allows for new materials, traits and modifiers to be added by other mods!