Getting Jah in Diablo 4 Season 15 takes patience, but there is a sensible way to improve your odds without wasting every spare resource. Jah is a Legendary Invocation rune that changes Evade into Teleport, giving many endgame builds the quick movement they need. If your setup depends on constant repositioning, keeping a steady supply of D4 items and rune materials can make the search feel far less frustrating.

Turn unwanted runes into new chances

The Jeweler is the key when Jah refuses to drop. In towns such as Kyovashad and the Kurast Bazaar, you can exchange three identical runes of the same rarity for one random rune from that tier. Three Cem runes or three Igni runes, plus the required gold, can become something completely different. It is not a quick guarantee, so do not spend every legendary rune immediately. Keep enough materials for several attempts, then use duplicates that do not fit your build.

Make every Undercity run count

Kurast Undercity should be the centre of your farming routine. Activate the Greater Tribute of Harmony before entering, then move with purpose. Defeat packs quickly, collect attunement, and avoid wandering through empty corridors. The reward chest improves as your attunement rises, so speed matters, but reckless play can cost more time than it saves. You will soon notice that a clean, steady route produces better results than rushing straight to the boss.

Do not ignore the extra encounter

Keep an eye out for the Portal Prankster. This Undercity-only treasure goblin does more than drop ordinary loot. Defeating it adds chests beside the exit portal once the dungeon is cleared. That makes a short detour worthwhile, especially when you are already using a Greater Tribute. Search likely side paths, listen for nearby activity, and do not leave the area simply because the main objective is complete.

Use mercenary rewards between runs

Mercenary rapport offers another steady source of runes. As your relationship improves through campaign missions and open-world activity, the vendor in the Mercenary Den unlocks more useful caches. They will not replace focused Undercity farming, but they help keep your crafting stock moving. A simple routine works well: spend the Tribute in Undercity, inspect every chest, return to the Jeweler, and check the mercenary vendor before starting another run. With spare materials ready, D4 items buy decisions become easier to plan while you work towards a Teleport-focused build.