To help balance the game, make it so players only lose life during their turn. This solves for the problem of simply waiting for the other player to die during your turn and incentivizes being quick with your turn. Mortals has not yet been played this way, and would require a small persistent signal to show Blinks actively losing life versus the ones frozen in their current game state.
Perhaps the team whose life is paused can have an additional circling white indicator, allowing you to perceive both the rate of breathing as well as indicating that it is not changing.