Psycho Soldier (English): Stage 5: Earth's Core
Athena has now plunged to the very depths of the Earth, itself, since all of these Shiguma monsters were sealed in this area. She now intents to reach very center of their base.
The lava here is no different from the water in Stage 4. Just don't fall into it, and don't touch any of its rising geysers.
How disgusting. At one point, it looks like you're forced to go through a Skull Field and lose your stats, and this is not too long before you finally reach the boss.
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For the boss, you must destroy a rock monster who can stretch his next. He is guarding a wall with a huge Alien mouth sticking out of it.
You destroy the monster, you also destroy the alien. This makes an opening that will commence the start of the final leg of Athena's adventure...