The Mountainside Dungeon is the setting for Grolla Seyfarth's stage in Rosenkreuzstilette Freudenstachel. The stage has a Ghosts n' Goblins motif, especially as shown near the end. At the end of the stage in the full game, Lucifer from Ghouls n' Ghosts is seen sitting in his throne, watching the player's fight against Grolla herself. It starts out in a small area in a mountainous region outside the dungeon, and takes the player through a dungeon filled with skeletons. The latter part of the stage is the same as that of the Ghost Town in the C75 Trial Version, which means that the dungeon is set near the Ghost Town itself, and therefore, located near Zeppelin's Castle.
- Das Dorf der Toten (The Village of the Dead)
- Rosenkreuzstilette ~Weißsilber~: Reencounter des Blutes (Reencounter Blood)
- Stage Theme (C76 Trials): "Dark Purple Moonlight" by Sky God Corridor
- Stage Theme (Ver. 0.06/Full Game): "Acid Rain" by Sound Prison
- Dialogue Theme: "Dark Purple Moon ~Dance of the Moon~ Rebirth" by Sky God Corridor
- Astaroth (Mini-Boss)
- Ball Bat
- Bloody Zombie
- Gargoyle Statue
- Skeletal Knight
- Skeletal Warrior
- Skull Cannon
- Snake Maker
The new hazards featured in this Grolla Stage start off with the falling spiked lamps that were seen in Liebea's Rosenkreuzstilette Stage and Schwer-Muta's ~Freudenstachel~ C75 Trial Stage, but these are silver with skulls painted on them. Next are the platforms placed over the spikes that also have skulls painted on them. When you land on these platforms, they will collapse, and if you stay on them for too long, they'll lower you into the bottomless pits and/or the spikes, instantly defeating the player character. Nevertheless, the later part of the stage keeps the same bloody rainstorm that the previous Grolla stage had in the C75 Trial. More recent versions add three new hazards in the form of mechanical spear traps that raise and lower the spears themselves as well as falling spiked platforms and platforms with bear traps stored inside (Wanaans, to be exact) that are set off once they're stepped on.
- The Mountainside Dungeon appears to be based on the inside areas of Ghosts n' Goblins and the castle dungeons in the Castlevania series.
- A large creature resembling a cross between a gargoyle and a dragon can be seen in the backdrop for the boss fight against Grolla at the end of the stage.
|Rosenkreuzstilette||Imperial Training Hall · Black Forest · Snowfield · Nosdu Mountains · Heiligtum des Wasserteufels · Luftfeste Sleipnir · Ghost Town · The Fortress City of Zuverburg · Research Tower · Schwarzer Kinderspielplatz · Zeppelin's Castle (Castle Entrance, Royal Chapel, Castle Bridge, Castle Keep) · Iris Palace (Labyrinth of Chains, Garden of Chaos, Iris Quarters, Iris Palace Sky) · Floating Island|
|Rosenkreuzstilette ~Freudenstachel~||Snow Chapel · Castle Grounds · Forest of God · Nosdu Mountains (C75 Trial) · Gruft der Feurdrache · Heiligtum des Wasserteufels (RKSF) · Luftfeste Sleipnir (RKSF) · Ghost Town (C75 Trial) · Mountainside Dungeon · Zuverburg Clock Tower · Research Tower (C75 Trial) · White Desert · Zeppy Ruins · Burkhardt Castle · Phalanx Cathedral Ruins · Battlefield · Library of Shadows · High Chapel · Iris Palace II (Sanctuary of God · Bloody Ruins · Dark Iris Quarters · Iris Palace II Sky) · Snowy Pillars|