▲
1
▼

Spoiler:The goal is to get to the top of the crystal tower without getting hit. Carrying the blue heart all the way to the top of the tower unlocks a door, which leads to the Book of Monsters. The Book of Monsters is a survival-like game mode accessible from the secrets menu.
Related Games
Cave Story
Cave Story's Secret Santa
Cave Story+
The Binding of Isaac: Rebirth
Ittle Dew 2
Senran Kagura: Shinovi Versus
2006 FIFA World Cup
Transformers: Fall of Cybertron
Star Wars: The Force Unleashed
Madden NFL 99
Kena: Bridge of Spirits
GeoSafari
Final Fantasy XIII
Twin Mirror
Ratatouille
Fight of Gods
LEGO Star Wars: The Force Awakens
Fallout 3
Rayman Arena
Freddy in Space 3: Chica in Space
Counter-Strike: Global Offensive
Far Cry: Primal
Injustice 2
OpenTTD
Dynasty Warriors 7
One Night at Flumpty's
Dead Space
Dead Rising
Goosebumps: Attack of the Mutant
Quake
Tony Hawk's Pro Skater 4
Street Fighter IV
Fez
LEGO The Incredibles
Final Fantasy XI Online
Cosmology of Kyoto
My Time at Sandrock
Hellblade: Senua's Sacrifice
SkiFree
Living Books: Green Eggs and Ham
Zombi
Indiana Jones and the Great Circle
Poker Night at the Inventory
Doom II: Hell on Earth
Dr. Robotnik's Mean Bean Machine
Mr. Krabs Overdoses on Ketamine
Sonic Forces
Marvel's Spider-Man: Miles Morales
Heavy Rain
That's Not My Neighbor