In-game Description

Research and unlock new monsters, to be created in the Hatchery.

Building Information

The Monster Locker is a building that allows the player to research and unlock new monsters. Each monster has a varying amount of Putty required to unlock. The Monster Locker must be built during the tutorial. It reaches a max level of four. Each level unlocks more monsters. The finished build unlocks four monsters: Pokey, Octo-ooze, Bolt, and Fink . The first upgrade (Lvl 2) unlocks: Eye-ra, Ichi, Bandito, Fang, and Vorg . The second upgrade (lvl 3) unlocks: Brain, Crabatron, Project X, Slimeattikus, and Zafreeti . The final upgrade (lvl 4) unlocks: Teratorn, Wormzer, and D.A.V.E. If the Monster Locker is destroyed while it is unlocking, it will delay the unlock time, and continue when it is repaired.

Upgrade Progression

Structure Level Resources Needed Upgrade Time Repair Time Resources Recycled Town Hall Level HP
Twigs-icon Twigs Pebbles-icon Pebbles Twigs-icon Twigs Pebbles-icon Pebbles
1 Twigs-icon 1,800 Pebbles-icon 2,300 10m Twigs-icon 900 Pebbles-icon 1,150 2 4,000
2 Twigs-icon 28,800 Pebbles-icon 18,400 5h Twigs-icon 15,300 Pebbles-icon 10,350 3 16,000
3 Twigs-icon 115,200 Pebbles-icon 147,200 20h 59m 15s Twigs-icon 72,900 Pebbles-icon 83,950 4 32,000
4 Twigs-icon 460,800 Pebbles-icon 588,800 8h 3h 33m 20s Twigs-icon 303,300 Pebbles-icon 378,350 5 64,000

Unlocking Monsters

Monster Locker Level Monster Image Monster Name Resources Needed Unlocking Time
- Pokey Pokey - -
1 Octo-ooze Octo-ooze Putty-icon 8,000 1hr
Bolt Bolt Putty-icon 16,000 2hr
Fink Fink Putty-icon 32,000 4hr
2 Eye-ra Eye-ra Putty-icon 64,000 8hr
Ichi Ichi Putty-icon 128,000 16hr
Bandito Bandito Putty-icon 256,000 1d 4hr
Fang Fang Putty-icon 512,000 1d 16hr
Vorg Vorg Putty-icon 384,000 1d 12h
3 Brain Brain Putty-icon 1,024,000 2d 4hr
Slimeattikus Slimeattikus Putty-icon 2,048,000 1d 12h
Crabatron Crabatron Putty-icon 2,048,000 2d 10hr
Project X Project X Putty-icon 4,096,000 2d 14hr
Zafreeti Zafreeti Putty-icon 6,192,000 2d 12hr
4 Teratorn Teratorn Putty-icon 4,096,000 2d 14hr
Wormzer Wormzer Putty-icon 4,096,000 2d 14hr
D.A.V.E. D.A.V.E. Putty-icon 8,192,000 3d

Building Progression

Structure Level Normal Damaged Destroyed
1 Monster Locker 1 Monster Locker Damaged 1 Monster Locker Destroyed
2 Monster Locker 2 Monster Locker Damaged 2
3 Monster Locker 3 Monster Locker Damaged 3
4 Monster Locker 4 Monster Locker Damaged 4


  • Its Inferno counterpart is the Strongbox, as they both can unlock monsters. The only difference is the size and shape, Strongbox is smaller and circular and the Monster locker is taller and of an oblong shape.
  • The speed up to complete unlocking a monster says training instead of unlock e.g.complete brain's TRAINING now.
  • In the beta stage of Backyard Monsters, players were able to build two Monster Lockers. Don't be surprised if you see two Lockers in one yard, fortunately they can only unlock one monster at a time. They're still given the advantage of having a longer NEC, though.
  • You can recycle the monster locker when it is unlocking but you will cancel the unlocking of what you are unlocking.
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