DynamicValue value = new PermanentsOnBattlefieldCount(filter);
int count = value.calculate(game, source, this) * 2;
Player player = game.getPlayer(source.getFirstTarget());
if (player != null) {
player.loseLife(count, game);
}
Player controller = game.getPlayer(source.getControllerId());
if (controller != null) {
controller.gainLife(count, game);
}