Diablo 4 PTR build testing lets you try Season 16 changes without levelling another character for days. Blizzard places a boost vendor called Mrak beside the main Waypoint in major cities. He can give you equipment, materials, levels, Paragon and seasonal items so you can start comparing setups.
The test runs from 27 October to 3 November 2026. Live-character copy is currently broken, so Mrak’s boosts are the quickest way to prepare a character. Here are the exact steps and test options.
How to start Diablo 4 PTR build testing
For Diablo 4 PTR build testing, open Diablo IV through Battle.net on PC. Use the game-version selector above Play, choose Public Test Realm, install the client and make a character. Choose a Seasonal character to test the new seasonal features.
- Find Mrak near a major city’s Waypoint.
- Choose boosts for level, Paragon, progression and equipment.
- Equip the weapons, Aspects, Talismans and skills you want to test.
- Run the same activity several times at a consistent difficulty.
- Change one item or skill and repeat the test.
Blizzard confirms account copying is broken in this test. Create a fresh character and use Mrak’s boosts instead. Our PTR known-issues guide covers the other bugs that affect testing.
What can Mrak give you in the PTR?
For Diablo 4 PTR build testing, Mrak can set you to level 70 and Paragon 200, grant Skill and Paragon points, unlock Waypoints and Torment tiers, and provide all Glyphs and maximum Glyph ranks. He can also give all Uniques, random Legendaries, Runes, Aspects and Talisman Items.
Materials, Obols, Lair Keys, War Plans progress, seasonal Horadric Items and Tyrael’s Boons boosts are available too. One catch: the equipment boosts only supply Helms at level 7 or above and Amulets at level 15 or above. If either item is missing, check your level first.
How to compare builds without wasting your test
For Diablo 4 PTR build testing, record your weapons, skills, Paragon, Talisman bonuses and difficulty. Repeat one encounter, change just one item or skill, then compare clear times, resource use and survivability.
Keep the test conditions consistent. With War Plans Tactics, compare several offered plans because activity and reward nodes affect probability, not guaranteed outcomes. See War Plans Tactics for node limits.
Which Season 16 bonuses are currently bugged?
Some Diablo 4 PTR build testing results are unreliable. Blizzard says Lair of Runes doesn’t currently increase rune drops from Lair Bosses. Warlock Flesh of Abaddon damage may require leaving and re-entering Demonform, and Paladin Horadric bonus damage against Weakened enemies fails to apply.
Druid Song of the Old Mountain still uses a 200% rather than 300% Petrify bonus; Rogue Spellbound Steel fails to increase Shadow Imbuement with Shadow Clone. Our Horadric Items guide covers intended requirements, and War Plans Points Missing on Alts covers the zone-change workaround.
How to report a PTR build bug
If Diablo 4 PTR build testing reveals something new, open the PTR menu with Esc and choose Report a Bug. Include your class, items, active bonuses, difficulty, exact actions and observed result. The test closes 3 November at 6 PM GMT, and Blizzard may adjust balance before the live release.
Our Season 16 PTR guide covers installation, while the Talisman guide and Tyrael’s Boons guide explain systems you’ll be testing. A repeatable result tells you more than an unverified best-build list.
Use Diablo 4 PTR build testing to compare effects you can reproduce. Record the PTR build version so you can test the same setup after Blizzard patches it.
Official source: Blizzard’s Diablo IV PTR instructions and boosts.
