Duel Strategies
In a two players game you should follow some slightly different approaches:
The biggest mistake is to play defensively. Don't hesitate, play as
quick as you can without losing control and put your adversary under
constant pressure. It is a good idea to attack as early as possible.
There are two basic strategies. The all-or-nothing strategy is to create
a gorge by purpose and wait for the red piece to really annoy someone.
While this method can be very efficient, it is also rather risky. An
alternative is to disturb the other player with one or two rows of
garbage over and over. This should be your method of choice if your pit
becomes full.
Erasing single rows will not affect your opponent. So if there is no
immediate need to do it, find another suitable place
for your piece and see if you can erase multiple rows later.
Try to keep an eye on the other pit. It is mean but effective to drop
your red piece while your adversary is busy with moving and rotating
near the ground.
If you recognize that you will lose soon but your opponent is in
troubles, too, you can try to play as slow as you can and let
someone else lose.
If you are playing against the computer, you have one problem and one
chance: The problem is that your opponent will definitely not get
disturbed. Your chance is that the algorithm is cautious and erases
a single row whenever possible.
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The most dangerous thing you should look out for are gorges.
To fill them perfectly you would have to wait for the long red piece which
will not appear just because you are waiting for it.
Another thing to worry about are bridges. They have to be
uncovered first before you can fill the holes below and erase those rows.
Often it is not possible to avoid a bridge. Try not to place much on it
so you can uncover the holes below sooner.
To avoid such difficult situations try to build compact structures.
You should be very careful when towering up a series of similar pieces.
A good choice to place your pieces are the walls of the pit.
This has the additional advantage to leave some room to move in the middle.
You can still move a piece on the ground for a short period of time if you
do not drop it, so you might want to slide it to fill holes in
your structure.
Do not build entirely plain areas even though it might look nice.
Leave some steps upwards and downwards. This allows you to
perfectly place any piece that might appear.