The Tempered State (Japanese 歴戦の個体 Rekisen no kotai, roughly "battle veteran specimen") is a phenomenon in monsters that heightens their aggression. Tempered Monsters are old, experienced monsters that have been living in the New World for a long time. From them living in the New World for so long, these monsters have gained the bioenergy of Elder Dragons. Every large monster in Monster Hunter: World and Iceborne can be affected by the Tempered State (including Elder Dragons, Subspecies, and Variants) except Great Jagras, Kulu-Ya-Ku, Tzitzi-Ya-Ku, Great Girros, Dodogama, Leshen, Ancient Leshen, Yian Garuga, and Shara Ishvalda.
Tempered monsters have a metallic sheen to their bodies, deal more damage, become enraged more often, enter powered-up states faster, and are resistant to Flash Pods. Tempered monster investigations can be unlocked by gathering traces of Tempered monsters and by breaking Tempered monster parts. Scoutflies glow blue instead of green when tracking a non-Elder Dragon Tempered monster or finding a trace of one. The icons of Tempered monsters have a purple outline.
Tempered monsters are necessary to get various types of items called Streamstones and Spiritvein Gems. Streamstones are obtained as rewards from High-Rank Tempered monster quests, while Spiritvein Gems are obtained from carves or shiny drops from Guiding Lands Tempered monsters. Streamstone Shards, Streamstones, and Gleaming Streamstones can be used to meld decorations, while Spiritvein Gem Shards, Spiritvein Gems, and Great Spiritvein Gems are used in augmenting Master Rank weapons and upgrading charms. Streamstones and Spiritvein Gems can also be used to unlock the limit of armor upgrades, allowing to increase their defense furthermore. Tempered monsters in the Guiding Lands drop special materials that are used in augments, charms, and some weapon upgrades.
Sullied Streamstones and Shining Streamstones can be appraised and they are converted into Warrior's Streamstones or Hero's Streamstones. Warrior's and Hero's Streamstones are used to augment fully-upgraded weapons; augments are special final upgrades for a weapon. There are five available options for HR weapons: Attack, Affinity, Defense, Slot Upgrade, and Health Regen. The amount of augments available depends on the weapon Rarity. Warrior's and Hero's Streamstones can be used to augment a specific pair of weapons classes: Sword (Great Sword and Long Sword), Blade (Sword and Shield and Dual Blades), Hammer (Hammer and Hunting Horn), Lance (Lance and Gunlance), Axe (Switch Axe and Charge Blade), Shaft (Insect Glaive and Bow) and Ranged (Light Bowgun and Heavy Bowgun).
List of Tempered Material Sources
This is a rough list of each Tempered material's sources, based on the rewards of their respective quests.
- Streamstone Shard: HR Threat Lv1 Tempered Monsters. (Pukei-Pukei, Barroth, Jyuratodus, Tobi-Kadachi, Anjanath, Rathian, Paolumu, and Radobaan)
- Streamstone: HR Threat Lv2 Tempered Monsters (Legiana, Odogaron, Rathalos, Azure Rathalos, Diablos, Black Diablos, Pink Rathian, Bazelgeuse, Deviljho, Lavasioth, Uragaan, and Ancient Leshen)
- Gleaming Streamstone: HR Threat Lv3 Tempered Monsters (Kirin, Nergigante, Teostra, Lunastra, Kushala Daora, Vaal Hazak, Behemoth, Xeno'jiiva, Kulve Taroth, Zorah Magdaros, and Ancient Leshen)
- Spiritvein Gem Shard: MR Threat Lv1 Tempered Monsters. (Pukei-Pukei, Coral Pukei-Pukei, Barroth, Jyuratodus, Tobi-Kadachi, Viper Tobi-Kadachi, Anjanath, Rathian, Pink Rathian, Paolumu, Nightshade Paolumu, Radobaan, Beotodus, and Banbaro)
- Spiritvein Gem: MR Threat Lv2 Tempered Monsters. (Legiana, Shrieking Legiana, Odogaron, Ebony Odogaron, Rathalos, Azure Rathalos, Diablos, Black Diablos, Lavasioth, Uragaan, Barioth, Nargacuga, Glavenus, Acidic Glavenus, Tigrex, Brute Tigrex, Brachydios, Fulgur Anjanath, Zinogre, and Scarred Yian Garuga)
- Great Spiritvein Gem: MR Threat Lv3 Tempered Monsters. (Kirin, Teostra, Lunastra, Kushala Daora, Velkhana, Seething Bazelgeuse, Blackveil Vaal Hazak, Namielle, Savage Deviljho, Gold Rathian, Silver Rathalos, Rajang, Stygian Zinogre and Ruiner Nergigante)
- Warrior's Streamstone: HR Threat Lv2 and Lv3 Tempered Monsters and Ancient Leshen.
- Hero's Streamstone: HR Threat Lv2 and Lv3 Tempered Monsters and Ancient Leshen.
Arch-Tempered Monsters (Japanese: 歴戦王) are even stronger versions of Tempered Monsters. They have a darker and more pronounced metallic sheen, have more health and deal more damage, sometimes have new behavior and attacks, and their icons' outlines are orange. So far, only HR Elder Dragons except Behemoth are known to be effected by the Arch-Tempered State. Arch-Tempered monsters are event-exclusive and their quests reward more streamstones than Tempered monsters and special tickets to craft γ (gamma) armor sets and layered armor sets.
- Tempered Deviljho and (Tempered) Extreme Behemoth are event-exclusive.
- Despite Extreme Behemoth being shown as a Tempered Monster, it is much stronger than even Arch-Tempered monsters.
- The 3.0 patch made Flash Pods less effective against Tempered Monsters, eventually having no effect with repeated use.
- Arch-Tempered Zorah Magdaros, Arch-Tempered Xeno'jiiva and Arch-Tempered Kulve Taroth are the only Arch-Tempered monsters without a regular Tempered version.
- Arch-Tempered Kulve Taroth and Nergigante have unique music.
- Pink Rathian is the only Tempered Monster that has a different threat level between quest ranks.
- Scarred Yian Garuga is the only monster that is exclusively Tempered.
- Arch-Tempered Kulve Taroth is the only Arch-Tempered monster to permanently replace its non-Tempered counterpart.
- Tempered Gold Rathian and Silver Rathalos were added in the first Iceborne title update.
- Tempered Ruiner Nergigante was added in the second Iceborne title update.
- Ancient Leshen is the only non-Tempered monster to reward Streamstones.
- On January 19th 2020 Capcom revealed the second part of the roadmap for Iceborne. The schedule indicates that Arch-Tempered monsters will return in Master Rank, starting from April 2020.