Fulgura Frango is a Genshin Impact Achievement under the Challenger: Series VIII series. You can get it by defeating the Millennial Pearl Seahorse while it's attempting to reconstruct a Xenomare Pearl.
This Achievement can be quite frustrating to unlock as it requires careful timing. It took me about seven times to complete it myself, so don't worry if it doesn't work out the first time around.
How to defeat the Millennial Pearl Seahorse while it's attempting to reconstruct a Xenomare Pearl in Genshin Impact
Before starting, you need to put together a team with the following:
- You need a Pyro, Cryo, or Dendro applicator to break the Millennial Pearl Seahorse's Pearl, which is the small Electro shield in front of its chest.
- You need a strong DPS unit preferably not reliant on summons or off-field auto attacks, as these could accidentally kill the boss too early.
Upon starting the battle, your goal is to break the Millennial Pearl Seahorse's Pearl—the small Electro shield in front of its chest. To do so, you must use Pyro, Cryo, or Dendro, and must specifically target the boss' chest. Be careful as the boss can be defeated without breaking the Electro shield. It should not die prematurely or you won't get the Achievement.
Once the Electro shield is removed, the Seahorse will fly into the air and summon three Pearl stations. Destroy all three Pearl stations using Reactions (again with Dendro, Cryo, or Pyro for the fastest results). Doing so will significantly weaken the boss.
At this stage, I strongly suggest not having any summons, off-field attacks, or anything that could prematurely defeat the boss. Your goal is to lower its HP until the point where you're able to do a one-hit KO later on. If you have a strong Ultimate ready, then save it for later.
As soon as the boss starts forming a Pearl (as pictured above), you must defeat it using one attack. It doesn't have to be an Ultimate, but having one helps. There's a few seconds window wherein the Pearl is forming. Once it has lapsed and the boss is still alive, you'll fail to get the Achievement and must restart the battle to try again.
If you manage to defeat the boss while it's forming the Pearl, you'll get the Fulgura Frango Challenger: Series VIII Achievement.
To get more Fontainian boss Achievements, check out our guide on How to get the Shackle Me, That I Might Willingly Be Destroyed Challenger Series VIII Achievement in Genshin Impact here on Pro Game Guides.