Copyright (c) 1977 Invicta
Ergo is played on an empty 9x10 square board:
The rules are displayed in this webpage (it's in German). I would like to thank Ralf Gering for pointing it out and also for translating the rules to English, from which I based this text.
Green's turn. The Green Lion at j1 can move to cell  and wins next turn. Black cannot stop it. Soldiers do not move diagonally.
Some hints (also described by Gering):
1) Try to force your opponent to place more
pieces than you. The pieces in your hand are
strongest. The player who is able to place the last piece
has an advantage.
2) If you block a row of three, do it at the edge (if possible) to get a lion.
3) Lions are strongest at the edge.
4) A broken three (similar to Renju) should always be blocked by putting a piece in the gap.
5) Balance attack and defense in the opening or you will lose early in the middle game.
6) The game is more strategic than you think. Build strong positions, such as Fours, and you will win, even if you don't see how.
7) Control the center and attack from the edge!