Honestly, the Proving Grounds trials don't get nearly enough love from the BL4 community and I think that's a tragedy. Everyone's obsessed with boss farming and Takedowns, which I get — those are flashy and the loot is obviously good — but the Trials are the single best source of dedicated class mod drops in the entire game, and they're also genuinely fun speedrun content once you learn the layouts. There are six Trials total, each one tied to a specific class mod that drops from the final boss, and each one is structured identically: three combat rooms with time limits, then a boss room. The twist that makes it worth your time is the True Trial mechanic — if you clear the entire Trial in under 5 minutes, you get double the chest room rewards and a guaranteed class mod drop from the boss. Not a chance. Guaranteed. I'm dead serious, this is THE place to farm class mods, and I wish I'd figured that out about 50 hours earlier than I did.
The time limit per room is 5 minutes individually, but the total completion time is what matters for True Trial eligibility. So you can take your time in rooms 1 and 2, absolutely blitz the boss room, and still hit the 5-minute mark. Each room has an objective — usually "kill X enemies" or "destroy X objects" — and the key insight for speedrunning is that you should ignore every single optional enemy. Sprint to the objective, kill only what you're forced to kill, and keep moving. The enemies will chase you, sure, but they don't need to die unless the objective requires it. I spent way too long fighting every mob in my early attempts and wondering why my clear times were 7-8 minutes. Once I adopted the speedrun mentality, I dropped to consistent 3:30-4:30 clears depending on the Trial.
All 6 Trials and Their Class Mod Drops
Trial of Survival — Drops the Survivor class mod for FL4K, which gives massive health regen and damage resistance when your pet is below 50% HP. The Trial itself is set in a Pandora canyon with mostly COV enemies, and the boss is a Badass Tink Tank that's honestly one of the easier boss fights — predictable attack patterns, no invulnerability phases, big crit spot on the mech's back. I consistently clear this in about 3:45 on Zane, making it my go-to when I just want quick class mods. The three rooms are: COV camp clear (ignore the tent enemies, only kill the marked targets), bridge defense (stand on the bridge and kill the 8 required rushers), and the boss arena. Survivor is a B-tier class mod for FL4K but the farm is so fast that it's worth it for the world drops alone.
Trial of Cunning — This one drops the Spiritual Driver class mod for Amara, and oh boy is this the one you want. Spiritual Driver applies your action skill element to yourself when you use your action skill — which sounds like a downside until you realize it triggers Mindfulness stacks, giving you up to 250% movement speed while you zoom around the map melting everything. The Trial is set in an Eridian ruin with Guardian enemies, and the boss is a Specter Prime variant with teleport attacks and hard-to-hit crit spots. The three rooms are: Guardian ambush (kill all marked enemies, about 12 of them), crystal defense (protect a crystal from three waves, use AOE weapons), and the boss. Clear time around 4:15 with practice. The Spiritual Driver is S-tier for Amara speed builds and absolutely worth farming a god roll.
Trial of Discipline — Drops the Stackbot class mod for FL4K, which increases critical hit damage by 5% per stack up to 500% but resets on body shot. The Trial is a Maliwan facility on Promethea, so shock-resistant shields are recommended. Boss is a Maliwan Deathsphere Commander — a bigger, angrier version of the floating orbs from the Takedown. Three rooms: troop clear (Maliwan infantry, kill 15 marked targets), generator destroy (three generators protected by Heavyweights), and boss. The generator room is the time-killer here — the Heavyweights have massive shields and you have to kill them before you can damage the generators. Use shock weapons. Clear time around 4:30. Stackbot is S-tier for FL4K crit builds, specifically Fade Away setups with high-damage single-shot weapons like the Monocle or the Headsplosion.
Trial of Fervor — Drops the Mind Sweeper class mod for Moze, which causes critical hits to spawn micro-grenades that deal splash damage. This thing is absolutely insane with Moze's splash damage scaling — those micro-grenades inherit all your splash bonuses, and with the right build they can chain-react through entire rooms. The Trial is set in a COV fortress on Eden-6, and honestly the swamp atmosphere combined with the COV aesthetic makes this the coolest-looking Trial by far. Boss is an Anointed Zealot with fire attacks. Three rooms: COV gauntlet (kill 20 marked enemies, these are the easiest rooms because COV just run at you), ritual interrupt (stand in three circles to interrupt COV rituals while enemies swarm), and boss. Clear time around 4:00. Mind Sweeper is S-tier for Moze, possibly the best class mod in the game for mobbing.
Trial of Supremacy — Drops the Seein' Dead class mod for Zane, and if you're playing Zane and you don't have this class mod, you're playing Zane wrong. Seein' Dead gives every shot a chance to activate all of Zane's kill skills, which means constant action skill uptime, constant movement speed, constant lifesteal — it's the engine that makes Zane builds work. The Trial is set in a corporate office on Promethea (Maliwan HQ aesthetic), boss is a Maliwan Executive with cloaking ability. Three rooms: office clear (kill 10 marked Maliwan execs), server room defense (protect three servers from waves of Maliwan soldiers), and boss. The server room is tricky because the enemies split their attacks between you and the servers, so you need AOE or a fast-moving build to cover all three positions. Clear time around 4:20. Seein' Dead is S-tier, mandatory for Zane. Farm this first if you play Zane.
Trial of Instinct — Drops Red Fang for FL4K, which makes your pet taunt all enemies on Gamma Burst activation. This is the survivability class mod for FL4K builds, and it single-handedly makes FL4K viable for solo Takedowns because your pet tanks everything while you DPS freely. The Trial is set in a wildlife preserve on Eden-6, lots of beast-type enemies. Boss is a Giant Jabber Alpha with summoning abilities (calls smaller Jabbers during the fight). Three rooms: beast hunt (kill 15 marked creatures), egg destroy (destroy 5 Jabber eggs before they hatch, ignore the adults), and boss. The egg room is a DPS check — if you can't destroy the eggs fast enough you get overwhelmed by hatchlings. AOE weapons recommended. Clear time around 4:45, the slowest of the six because the Jabber Alpha boss has an invulnerability phase when summoning adds. Red Fang is A-tier for FL4K, essential for any solo endgame content. Check our endgame guide for how these class mods fit into full builds.
Speedrun Builds and Chest Room Strategy
The chest room at the end of each Trial contains four chests, and on M10 each chest has a 1-2 legendary drop rate. Plus the boss drops their guaranteed class mod if you hit the True Trial time. The total haul per sub-5-minute run is typically 6-10 legendaries: 4-8 from chests, 1-3 from the boss. The speedrun builds that make this efficient vary by character. Zane's Violent Momentum skill combined with a Snowdrift artifact gives you roughly 200% movement speed — you literally outrun enemy projectiles — and the Clone can clear objectives while you're sprinting to the next room. Amara's Spiritual Driver plus Mindfulness stacking is even faster at roughly 250% movement speed, though the self-damage effect means you need to manage your health more carefully. For Moze and FL4K, you're slower but you kill bosses faster, so the total clear time balance is roughly similar across all four Vault Hunters if you're built optimally. Check our builds database for specific speedrun loadouts and our Proving Grounds overview for how Trials fit into the broader endgame loop.