Golden Beetle first appears as a sub-boss found in the Arqa Block on the 47th floor of Tartarus, encountered in a group of three. They impede the player's progress and must be beaten to proceed. They are later encountered as normal enemies in the Yabbashah Block of Tartarus, from floors 78 to 89.
The boss fight with the Golden Beetles always begins with the Beetles each getting a free turn, which they will use to cast Tarukaja on themselves. They also possess high defense, which makes it difficult to damage them. Bring Akihiko and Personas that know Zio spells to exploit their weakness to Electricity and gain easy All-Out Attacks. While not set as a weakness, these Golden Beetles take 25% additional damage from Fire and Wind attacks.
The Shadow is known as the Strength Beetle in Persona 4 and appears in Chapters 5 and 6 of the Void Quest within the Midnight Channel. Upon being defeated, they may drop the Golden Horn material. Selling 6 Golden Horns at Daidara will unlock the Plate Mail male armor in the shop.
The Golden Beetle is an F.O.E fought for the request, Investigate You in Wonderland, to obtain the Yellow Orb Key item, the Sphere of Fecundity, from the void behind it. Completing the quest nets the Merit Badge, an accessory which grants +10 to HP and SP and +1 to all stats. The Bug Gold it drops allows Theodore to create the Silence Bow for Yukari, which inflicts Magic Bind, Heavy Punch for Akihiko, which inflicts Agility Bind, Cobra Boots for Chie, which inflict Poison, and Drowsy Shield for Kanji, which inflicts Sleep, each with a 15% chance to inflict their respective ailments.