Nidhogg

Each player arranges creatures they control in
a sequence. Only the first creature in a sequence
can, and must, attack or block if able.
At the end of each combat phase, if a player
controls a creature that attacked this turn,
untap that creature and there is an additional
combat phase after this one.
Whenever an player is dealt combat damage,
if they control no creatures, that player loses
the game.