The set up for Onitama is random and uniform so there is no strategy to be played until your first move – so I will jump right in:
During The Game:
Control the line in front; This is a game about blocking off your opponent’s next move and keeping your master safe. The brilliance of this game is that all the moves are on the cards in front of you and are all public information. If you can see where your opponent can move, you can restrict those options and force the move. In other words, look to the four or so spaces the opponent can move and take the move that allows for the capture of any piece that moves there.
The other way of looking at this tactic is to control the line in front of you – those 5 spaces that offer the best vantage for attack. If you have control of these spaces then it’s more difficult for your opponent to launch an attack. You can use this too push forward (see below).
Identify the unique card & keep it; Generally of the five cards there is one really distinct card – perhaps the one that has a diagonal move in both directions forward or the one that allows you to jump two spaces forward. These distinct cards offer a unique vantage. If you trade them, they will likely be the opportunity your opponent needs. Try to hold on to this card as long as you can and use them to gain the upper hand. These cards are often linked to the first strategy and allow you to control the line whilst preventing your opponent.
Push forward for the “way of the stream”; Pushing forward was part of the first tactic – it’s important because the opponent’s master can always move, but their castle cannot. Taking the way of the stream and capturing their base is a positive way of playing the game. Putting your opponent on defence may also help you to create the opportunity to take the master. Just be careful that your advances don’t backfire!
Don’t be afraid to use your master; Even whilst being careful, using the master is key. You won’t win this fight with one piece tied behind your back and that means you need the master on the front foot. You can keep him supporting or allowing the counter take to any advance by your opponent, but if you can get your master into the front line then you can more nimbly launch that attack for the opponents base when the opportunity arises.
Remember to jump; Some cards allow you to move further than your adjacent square. In this game each piece acts like the knight and jumps (rather than passing through spaces as the bishop would). Taking advantage of this can help you launch surprise attacks. Even using your own pieces as a false shield or allowing the counter-take (after an opponent captures your piece) from this jump move, can trick your opponent into a simple mistake that gives you the upper hand.
Force your opponent to one side; Last but not least – push your opponent to one side. Typically the cards are asymmetric, and your opponent may be commonly using a card that is driving their pieces to one side of the board. It’s okay for a while, but suddenly they can’t move further left/right and that card has limited value, nonetheless you pass it to them and they might have to release the card they have been holding back or slip into a position that is easier for you to dominate / control the line.
With that – all the best, and let me know your tips and thoughts!