Poison is one of the most interesting ways to clear enemies in ARPGs, with building stacks and increasing damage over time always a puzzle. The Acid Flask in Last Epoch is the baseline of the Rogue’s poison kit, so let’s make it work in the full build.
Acid Flask Poison Rogue build details in Last Epoch
As you might expect, the best Acid Flask Rogue Build in Last Epoch is a poison-stacking build. It utilizes the incredibly effective Poison Pools ability from the Acid Flask’s specialization tree to wrack up damage and damage over time stacks.
Best Rogue Mastery for Acid Flask
Our recommended Rogue Mastery for Acid Flask Rogues is Falconer, basically only because of its ability to increase Damage Over Time by 49 percent. While the Bladedancer and Marksman can both improve poison chance, the Falconer’s Falcon applying additional stacks for you to enemies you don’t see is critical. With the extra attack speed and Haste stacking available to a Falconer, we can stay safe while letting poison ticks take care of foes.
Acid Flask is a base Rogue Talent, so theoretically any Rogue Mastery can use it effectively. We like the Falconer since the Falcon serves as an additional method of building Poison stacks. You’ll have more than 200 or more percent Poison chance on most builds, and your Falcon inherits 50 percent of that, so it’ll be more than capable of tearing through enemies. In addition, the Acid Flask Rogue lacks a nice, consistent way to apply stacks at a range without dead-on hitting enemies with Flasks. The Bird helps out there.
However, that isn’t to say that there aren’t benefits to Bladedancer or even Marksman for this Last Epoch setup. Just not as many as we’d like.
Best Skills and Specializations for Acid Flask Rogues
We recommend the following Specializations for Acid Flask-focused Rogue builds:
| Skill Name | Specialization Node Name |
| Acid Flask | Caustic Concoction Two, Contamination Four, Poison Pools One, Hydrochloric Acid Five, Lingering Toxicity Three, Amatoxic Pools Four, Corrosive One |
| Puncture | Timing Two, Penumbral Ambush One, Scalebane One, Perforate Two, Press the Attack One, Toxic Delivery Three, Effacious Toxin Five, Rapid Strikes One, Bloodthirst Four |
| Shift | Shadow Recuperation Two, Sleight of Hand Five, Swift Recovery Three, Shadowslip One, Elusive One, Parting Gift Two, Arrival Gift Two, Momentum One, Velocity Three |
| Shuriken | Alacrity Three, Fan of Blades One, Blade Shield One, Floating Blades Three, Bladed Armor Three, Abrasive Arsenal Four, Toxic Tips Four, Entry Points One |
| Falconry | Falconer’s Journey One, Is it a bird? One, Agile Prey Two, Rending Talons Four, Falconer’s Mark Two, Avian Stamina Four, Hunter’s Spoils One, Bird of Prey Two, The Blood Dance Two, Wake of Wings One |
Of course, Acid Flask makes its appearance on our Specialization list. Your goal is to stick around in Acid Pools to proc Hydrochloric Acid, giving huge bonuses to poison. As enemies stay in the poison, you’ll be building dozens of stacks per second. Shift also dumps Acid Flasks on the floor, allowing you to spread the love around the battlefield. Poison Rogues don’t have fantastic ways to automatically spread their Damage Over Time, so make sure you place your pools carefully.
Puncture isn’t seen in every build, but it has a particular purpose: Scalebane and Bloodthirst. This combo turns all your Bleed chance into Poison chance and all of your Physical Shred into Poison Shred, while Bloodthirst gives you huge buffs to Poison Chance. You’re going to be in the thick of combat with this Acid Flask build to make good use of your Pools.
Since Shuriken are automatically used whenever we Shift, our last ability is Decoy. This ability is perfect for an Acid Flask Rogue, since it lets you guide enemies into a Pool of choice.
An alternative to Shuriken and Decoy is Explosive Trap. Explosive Trap has a five-point Specialization called Instrument of the Alchemist, which causes your Explosive Traps to have a small chance to fling an Acid Flask. This is a natural way to spread pools around the battlefield but requires you to hit a 30 percent proc window—at maximum. We decided not to go with this to focus instead on durability, but this is a very reasonable option.
Best Acid Flask Rogue Passives and Gear
We recommend the following passives for the Rogue Acid Flask build:
| Tree Name | Passive Name |
| Rogue | Swift Assassin Eight, Guile One, Evasion One, Agility Five, Poison Tipped Eight |
| Falconer | Raptor’s Wings Five, Handler Eight, Peltast Seven, Avian Hurl Six, Evasion Tactics Four, Relentless Talons Five, Sky Assassin Seven, Stymphalian Feathers Five, Expediency Five, Tailwind Six, Coordinated Fade One, Crimson Skies Five, Fencing Grace Seven, Deflect and Weave Five, Poise Five, Wilderness Scout Three, Stamina of the Rover Six |
The Rogue’s Poison Tipped ability is the only part of the Rogue tree we care about, other than the obvious choices of Agility Two and Swift Assassin Eight. Poison Tipped does mean our preferred build is a Dagger and Shield.
The Falconer Tree only has one ability which strictly buffs poison, called Sky Assassin. This Skill is a 49 percent damage boost for our primary damage. The rest of the Falconer’s tree prioritizes landing additional hits through Haste and your Falcon as well as giving you exceptional durability. We also recommend getting Crimson Skies, since our Scalebane ability will turn Crimson Shroud’s chance into Poison chance.
As for Gear, prioritize Increased Poison Damage. Attack Speed and Increased Damage Over Time are very valid additional affixes, but you’ll usually get more value out of the more specific Poison. Be sure to augment your Mana regeneration through affixes or armor pieces, since you burn through Mana quite quickly through Shift and Flask spam.
Once you reach endgame, you’re really going to want Drought’s Release. This Kris improves your Acid Flask significantly, with plus one Level to it and a huge bump to Poison Damage. The Blood Roost Unique gloves work excellently for an Acid Flask build, improving your Bleed chance—and thus, your Poison chance—significantly.
