This will surly challenge even the best puzzles heads. Simple but perfect.

One metal door that's locked with a security code that you need to unlock.

The grid has 9 heads that turn red or blue. Tap any head to turn it the opposite color, other heads but not all, will also turn the other color. When you have made all the heads blue.
Now make them all red. The pattern of nearby heads will also change.

Unlock both levels to unlock the door to revive the GOLD.

Good Luck.

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