The total slot count will remain the same. This means the target item must be at minimum 1 slot with 1 regular augment attached to it. The fodder item will lose 1 slot for every SGA transferred while keeping all regular augments. If the item is a 1 slot with only the SGA installed, it will become 0 slot. First extra slot augment is ruiner nergigante. Second one is tempered rajang. Third one is both Tempered stygian zinogre and tempered ruiner nergigante. So, Anywhere, Volcanic, Tundra. Keeping Volcanic and tundra maxed will let you get all the materials for extra slots augments. Slot Upgrade augmentation is a toss-up. If you need an extra medium, sure. Basic Augments which you can’t be sad about Don’t take affinity on weapons with high base affinity – swap to Attack Boost.

Fully upgraded weapons and armors can be augmented to further enhance their power. Augmentations require rare monster materials and Streamstones. Streamstones can be obtained by completing Tempered Investigation.

Tempered Investigation

Tempered Investigation quests are randomly awarded when the player gathered tracks from tempered monsters.

Threat LevelMonsters
1Pukei-Pukei, Tobi-Kadachi, Anjanath, Barroth, Jyuratodus, Rathian, Paolumu, Radobaan
2Rathalos, Azure Rathalos, Pink Rathian, Diablos, Black Diablos, Bazelgeuse, Uragaan, Lavasioth, Legiana, Odogaron
3Kirin, Teostra, Kushala Daora, Nergigante, Vaal Hazak

The following monsters do not have Tempered variation: Great Jagras, Kulu-Ya-ku, Tzitzi-Ya-Ku, Great Girros, Dodogama, Zorah Magdaros, Xeno'jiiva

Tempered Investigation Reward

Completing tempered investigations reward the player with various streamstones and feystones. Streamstones are used for augmentations, feystones can be appraised and yield decorations.

Investigation TypeQuest RewardsBonus Reward (Purple)
Threat IStreamstone Shard (7%)
  • Mysterious Feystone (60%)
  • Glowing Feystone(35%)
  • Worn Feystone (5%)
Threat IIStreamstone (7%)
  • Glowing Feystone(36%)
  • Worn Feystone (35%)
  • Warped Feystone (26%)
  • Sullied Streamstone (3%)
Threat IIIGleaming Streamstone (7%)
  • Worn Feystone (72%)
  • Warped Feystone (13%)
  • Sullied Streamstone (12%)
  • Shining Streamstone (3%)

Streamstone

Streamstone shard, streamstone, and gleaming streamstone are used as:

ExtraExtra Augment Slots Mhw
  • Key ingredient for Melding Pot
  • Primary ingredient for Armor Augmentation
  • Secondary ingredient for Weapon Augmentation

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Sullied Streamstone and Shining Streamstone will be appraised and identified as Warrior's streamstone and Hero's streamstone. Warrior's streamstone and Hero's streamstone are the primary ingredient for weapon augmentation.

Sullied StreamstoneShining StreamstoneAugmented Weapon
Warrior's Streamstone: SwordHero's Streamstone: SwordGreat Sword, Long Sword
Warrior's Streamstone: BladeHero's Streamstone: BladeSword & Shield, Dual Blade
Warrior's Streamstone: HammerHero's Streamstone: HammerHammer, Hunting Horn
Warrior's Streamstone: LanceHero's Streamstone: LanceLance, Gunlance
Warrior's Streamstone: AxeHero's Streamstone: AxeSwitch Axe, Charge Blade
Warrior's Streamstone: ShaftHero's Streamstone: ShaftInsect Glaive, Bow
Warrior's Streamstone: RangedHero's Streamstone: RangedLight Bowgun, Heavy Bowgun

Weapon Augmentation

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Fully upgraded weapons can be augmented to further enhance their capability. The following augmentations can be added to weapons:

Augmentation TypeDescriptionEffect
Attack IncreaseIncrease attack power. Stacks with other upgrades+5 True Attack Value
Affinity IncreaseIncrease affinity. Stacks with other upgrades+10% affinity (+5 for 2nd and 3rd affinity augmentation)
Defense IncreaseIncrease defense and adds a chance to reduce damage taken each time you receive damage. Stacks with other upgrades+10 defense
Slot UpgradeAdds an extra slot. Stack with other upgrades to increase the slot's level
Health RegenRegain health as you land attacks. Stack with other upgrades to increase the amount of health regained
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Weapon augmentations can be overwrite; however, materials used for previous augmentation will not be returned. Weapons of different rarity requires different materials to add augmentations:

RarityAugmentation SlotMaterials required per Augmentation
63
  • Warrior's Streamstone x1
  • Streamstone Shard x3
  • Rare Monster Material
72
  • Warrior's Streamstone x2
  • Streamstone x3
  • Rare Monster Material
81
  • Hero's Streamstone x1
  • Gleaming Streamstone x3
  • Rare Monster Material
Augmentation TypeRarity 6Rarity 7Rarity 8
Attack IncreaseRathalos Plate x2Rathalos Ruby x1Teostra Gem x1
Affinity IncreaseOdogaron Plate x2Odogaron Gem x1Kushala Gem x1
Defense IncreaseBird Wyvern Gem x1Wyvern Gem x1Elder Dragon Blood x2
Slot UpgradeLegiana Plate x2Legiana Gem x1Vaal Hazak Gem x1
Health RegenAnjanath Plate x2Anjanath Gem x1Nergigante Gem x1
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Armor Augmentation

Armor augmentation has one single option: Upgrade Limit Removal. This augmentation increase the maximum upgrade limit for the armor; allowing the armor to increase its defense.

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RarityStreamstone Required
6 and belowStreamstone Shard x1
7Streamstone x1
8Gleaming Streamstone x1