How to Beat Rey Dau in MH Wilds: Thunder Apex Weakness

Rey Dau is the thunder-charged apex predator of the Windward Plains and one of the toughest story fights in Monster Hunter Wilds. It shows up in Chapter 2 during “The Eye of the Storm,” so your gear will be mid-game — preparation matters.

Weaknesses and weak point

• Best elements: Ice (highly effective), then Water. Rey Dau resists Thunder (do not bring a thunder weapon) and Shock Traps do nothing.
• Weak point: the head, breakable, and the wings and tail are breakable/severable.
• Its head is often exposed right after a discharge attack — that is your window to unload.

The thunder threats

Rey Dau inflicts Thunderblight, which makes you easier to stun; evade repeatedly to clear it, or use a Nulberry. It also has a Weak Roar that briefly immobilizes you — Earplugs help. Both are why thunder-resistant armor and a Nulberry stack are recommended even if your defense is otherwise fine.

The fulgurite mantle

When a charged wing or tail touches the ground, it reacts and forms a mantle of fulgurite around the appendage. This widens its attack range and increases its charging capacity — so make breaking those parts a priority. After a big lightning release, Rey Dau gets stuck briefly, and that is your free damage window.

Fight flow

Rey Dau roams toward its nest (Area 17) and loops back, so the encounter is mobile. Use the Environment Overview screen to track it, and let it come to you rather than chasing. After the story fight it becomes a recurring High Rank hunt, and as a Tempered monster it is a solid source of decorations — see the tempered investigations guide.

Bring Ice or Water damage, thunder resistance, Nulberries, and Flash Pods. The full weakness chart lists where Rey Dau sits among the roster, and the elemental vs raw guide explains why Ice outperforms raw here.