The Flame Sac and Inferno Sac are monster materials that youll need to build some powerful fire items in Monster Hunter Wilds. But youll need to fell some of the games fire-breathing creatures before you can get your hands on them.In this Monster Hunter Wilds guide, well walk you through how to get Flame Sacs and Inferno Sacs, as well as what you can craft with them.How to get Flame Sac and Inferno Sac in Monster Hunter WildsThe Flame Sac is a Low Rank material that exclusively comes from the Guardian Rathalos, which youll encounter toward the end of the main campaign, once you reach the Ruins of Wyveria. Its an infrequent carve from the monster, and will only drop about 20% of the time. Notably, the other Low Rank fire monster, Quematrice, cannot drop a Flame Sac and uses a different mechanism to create its flame attacks.The Inferno Sac is the High Rank version of the Flame Sac, and comes from far more monsters than its predecessor. Here are all the High Rank monsters that can drop an Inferno Sac in Monster Hunter Wilds:Yian Kut-KuRathianRathalosGuardian RathalosGraviosEach time you kill these monsters youll have a small chance to get their Flame Sac or Inferno Sac, depending on which they drop.What to use Flame Sac and Inferno Sac for in Monster Hunter WildsThe Flame Sac and Inferno Sac are primarily used for crafting fire weapons and armor based on fire monsters go figure.In Low Rank, youll need a Flame Sac from the Guardian Rathalos to build any weapons in the Guardian Rathalos tree that deal fire damage. Hammer enjoyers, for example, will need three Guardian Rathalos Scales, two Guardian Rathalos Webbing, and one Flame Sac in order to craft the Albirath Bludgeon. You wont need any Flame Sacs to build the Guardian Rathalos armor set.In High Rank, youll need an Inferno Sac for multiple different projects, including some pieces of the Kut-Ku armor set, Kut-Ku weapons, Quematrice weapons (funnily enough, considering it doesnt drop any), High Rank upgrades to your Low Rank fire weapons, and more.Need help navigating the Forbidden Lands? OurMonster Hunter Wildsguides can outline your progress with ourmain story walkthroughandmonster listahead of reachingHigh Rank, help you settle on an armament with ourweapons listandbest weaponsexplainers, and teach you how to uncoverores,bones, and getmonster tails.