Hnefatafl is an ancient game from Scandinavia, that is also known as Viking Chess, even though it is older than chess.
In this games two sides play against each other with differently sized armies. The white player controls the King and his defenders and tries to escape while the black player controls the invaders and tries to capture the King.
The original rules are lost but there have been many attempts to recreate them, which is why there are many variants played of this game today. These differ by many aspects, the biggest one being the board size which can range from a 7x7 board over the usual 11x11 board up the the gigantic 19x19 board.
This game supports many different Hnefatafl variants, such as:
This variant was created to solve many problems that were discovered while trying to recreate the original rules. One big addition is the rule of the Shieldwall where blockades at the edge of the board can be destroyed. Or the Exit Fort which allows the King to escape over the edge of the board instead.
Basecamps were added to this variants, which can't be added by the defender and therefore limit the path to escape for the King but also restrict the movement of the attackers, making it a quite tactical variant.
A fun variant created by the Tafl community which allows moving a piece multiple times if each move results in a capture of enemy pieces. It also introduces two new, stronger pieces and allows them and the King to jump over other pieces, changing the usual blocking tactics.
This variant has an armed King who can capture pieces himself and also escapes by reaching the edge. He is weaker though as he can be captured by two pieces instead of four.
Similar to the Berserk rules it contains jumping pieces but also introduces a new type of unit: The Variengated Men (or Mercenary). Instead of getting captured when surrounded he just switches side, causing chaos all around.
Besides those and many other already defined variants new ones can be created and be played offline and online against other players.