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There is really only one reason you need to go here, and that is for HM04: Strength. There are a few other items here, but the trainers are fairly weak, so grab what you need, battling the trainers along the way. On the fifth floor you will see two old ladies. One will give you HM04: Strength. The other lady will give you a Cleanse Tag. This item, when held by your lead Pokémon, reduces wild Pokémon encounters by 50%. You're done here for now, so go ahead and head on out!

[edit] Wild Pokémon

Pokémon Found on the First Two Floors

Pokémon	Version	Type	Morning	Midday	Night
Gastly	Diamond and Pearl	/	Many	Many	Many
Misdreavus	Pearl Only		None	None	Some
Murkrow	Diamond Only	/	None	None	Some
Zubat	Diamond and Pearl	/	Many	Many	Many

Pokémon Found on Floor Three

Pokémon	Version	Type	Morning	Midday	Night
Gastly	Diamond and Pearl	/	Many	Many	Many
Golbat	Diamond and Pearl	/	Rare	Rare	Rare
Misdreavus	Pearl Only		None	None	Some
Murkrow	Diamond Only	/	None	None	Some
Zubat	Diamond and Pearl	/	Many	Many	Many

Pokémon Found on Floor Four

Pokémon	Version	Type	Morning	Midday	Night
Gastly	Diamond and Pearl	/	Many	Many	Many
Golbat	Diamond and Pearl	/	Few	Few	Few
Misdreavus	Pearl Only		None	None	Some
Murkrow	Diamond Only	/	None	None	Some
Zubat	Diamond and Pearl	/	Many	Many	Many

Pokémon Found on Floor Five

Pokémon	Version	Type	Morning	Midday	Night
Gastly	Diamond and Pearl	/	Many	Many	Many
Golbat	Diamond and Pearl	/	Some	Some	Some
Misdreavus	Pearl Only		None	None	Some
Murkrow	Diamond Only	/	None	None	Some
Zubat	Diamond and Pearl	/	Many	Many	Many

[edit] Items

• HM04:Strength: Talk to a lady on the fifth floor to receive HM04.
• Revive: There is a Revive in the bottom left-hand corner of the third floor.
• Cleanse Tag: Talk to a lady on the fifth floor to receive the Cleanse Tag.
• Oval Stone: This is in the middle of the second floor, right in front of the trainer.
• TM 27 (Return): This is near the middle of the bottom side of the fourth floor.