Board Thread:Questions and Answers/@comment-34352806-20180115182219/@comment-30871204-20180116024241

27 is when you stop unlocking.

Reccomended:

Coin (more probable):

Prototype, Shotgun Minigun, Hellraiser, Fireball spell

Gem (requires grinding):

Adamant laser cannon, Zues Chain sword

Free (ish):

Soulstone, Void ray rifle, flag keeper, veteran