Setup

Place any tile with the add (+) action facup on the table: this is the start of the waterfall.

Give all players 4 tiles and 1 Pawn. Everyone places the pawn above the waterfall.

The remaining tiles become the facedown draw pile.

Example game setup (for 2 players, to keep it simple).

Objective

The game ends when when the waterfall has 20(+) cards or the deck is empty (rare). Sum your scored tiles: highest score wins!

Gameplay

From start player, take clockwise turns until the game ends.

On your turn, you first play cards and then fall down the waterfall.

Example of a simple turn: playing cards and then falling down that number of steps.

PLAY: Play as many hand cards as you want.

Sum the numbers on them. That is how many spaces you’re allowed to fall.
If you have no tile in hand, move a single space and draw a tile.

FALL: For every space you move, pick one of the positions below your current tile (down left or down right).

It has a tile? Execute its action!
It’s empty? You’ve exited the waterfall. Reset to the top; your turn is over.

You can’t enter a tile that contains another player, unless both your options are blocked.

Actions

Everything in this game happens by executing a tile’s action (when you visit it). The main actions are ADD, DRAW and SCORE.

When you do an ADD action,

Place 1 tile from your hand in the waterfall (a pyramid shape).
Adjacent to an existing tile.

The DRAW action allows drawing 3 cards from the top of the facedown deck, into your hand. If the deck runs out, shuffle the discarded tiles and make it the new deck.

The SCORE action works as follows. You may score at most 2 tiles this way (with one SCORE action).

Check the gemstones that you visited thus far (when falling down this turn).
Pick a tile from your hand that has a matching gemstone. (If none exists, just do nothing.)
Place that tile facedown in your score pile. Its number scores you points at the end of the game.