Nidhögg the Thundering

The power of lightning dances along the blade of this sword, a promise of the pain to come.
Overview

Unlike ordinary weapon upgrades, enchanting this sword replaces any existing improvements on the base Nidhögg. In practice, that means the enchantment starts from its own upgrade track rather than preserving the enhancement level of the normal sword. As a result, players should plan their crafting materials carefully before converting the weapon.
Its upgrade progression is as follows:
- Quality 1: 135 slash, 10 lightning, 200 durability
- Quality 2: 141 slash, 10 lightning, 250 durability
- Quality 3: 147 slash, 10 lightning, 300 durability
- Quality 4: 153 slash, 10 lightning, 350 durability
The crafting costs for each level are:
- Quality 1: 1 Nidhögg, 6
Flametal, 1
Iolite
- Quality 2: 6 Flametal, 1 Iolite
- Quality 3: 12 Flametal, 2 Iolite
- Quality 4: 18 Flametal, 3 Iolite
The full upgrade path therefore costs 1 Nidhögg, 42 Flametal, and 6 Iolites in total. However, only Quality 2 is currently obtainable as of patch 218.15, which makes the immediate practical investment much lower: just 6 Flametal and 1 Iolite beyond the base weapon and enchantment cost.
Because the lightning effect is chance-based rather than guaranteed, Nidhögg the Thundering performs best when used against groups or clustered enemies, where chain lightning can contribute extra damage beyond the initial strike. Its reliable slash damage still makes it effective as a general-purpose sword, while the elemental component adds value against enemies vulnerable to lightning.
Official description
The power of lightning dances along the blade of this sword, a promise of the pain to come.