Onami can be played with some tweaks to the original rules that you may want to try out. The following are game play variations that we have come up with and have been suggested by Onami fans.
BALANCING STARTER TILE
For 2,3,4 & 6 player games, draw a card from the deck FACE DOWN on the center square of the board. Spin the card in a random direction and then flip it over. This tile plays as any other would on future player's turns. The first time an adjacent card overpowers it, place the appropriate token/die on it.
This balances the number of turns per player. Under normal rules, in all but 5-player games, the first player gets an extra turn and is always last. The Starting Tile "fixes" this.
SLEEPING ISLANDS
The first round, each player places a card from their hand on the board FACE DOWN anywhere on the board with their color token on it. Replenish your hand as normal.
While face down this is a island that can not be overpowered. You will want the card you choose to be strategic for your end game.
This is your SLEEPING ISLAND. On any turn after the first, instead of playing a card from your hand, you may AWAKEN YOUR ISLAND. When you Awaken the island you flip that card over and orient it in any direction you wish. This then plays as normal, triggering whatever waves occur in all four adjacencies. On the turn you awaken your island, you do not draw a card.
If you have not awakened your sleeping island by the time last card is placed it stays asleep and the game ends.
+ WALL
During game setup place 5 cards FACE DOWN forming a PLUS + in the center of the gameboard. No one ever claims these squares, they act as gameboard borders for the rules of how waves capture. Otherwise, play the game as normal.