It takes two to Tango and only one to end the game.

[Awesome Adam]

I've mentioned this before, and honestly, I've been too lazy to research it, to figure out if it was an official rule, or something we house ruled without realising it.

The game ends immediately when there is only one warband remaining on the table. Any treasures not already removed from the table are lost.

We've always played that way. I taught the rest of my group how to play Frostgrave, it's never been questioned and at this point I honestly can't recall if I decided to house rule that for balance, or just assumed it, but it works well.

Less shooty wizards can focus on getting warbands with treasures off the board as fast as possible and deny their opponents unlcaimed treasures.
Shooty wizards have to balance between scoring with treasures and kills.

[Timeshadow]

I've mentioned this before, and honestly, I've been too lazy to research it, to figure out if it was an official rule, or something we house ruled without realising it.

The game ends immediately when there is only one warband remaining on the table. Any treasures not already removed from the table are lost.

We've always played that way. I taught the rest of my group how to play Frostgrave, it's never been questioned and at this point I honestly can't recall if I decided to house rule that for balance, or just assumed it, but it works well.

Less shooty wizards can focus on getting warbands with treasures off the board as fast as possible and deny their opponents unlcaimed treasures.
Shooty wizards have to balance between scoring with treasures and kills.

In the rules any treasure left on the table is calmed by the remaining warband. That is a house rule many people play with though.

[Plus Four]

It's a house rule - although, as Timeshadow says, lots of people have adopted this mechanism to prevent shooty wizards just clearing the board!

[Awesome Adam]

Thank you for clarifying that.

I still highly recommend it use, as it makes "kill all opponents on the board" style of play less attractive.

[jp1885]

We steer a middle path - if there's only one warband left, it gets all remaining treasures that it's realistic for it to get. In our last game, mine was the last band standing, but was decimated by skeletons and it wasn't feasible for my remnants to fight through them to get to the remaining treasure, so it was deemed lost.

[Verhalvalla]

I might suggest that if one band is wiped off the table, then the remaining warband may collect as many unclaimed treasures as it has models left on the table not carrying treasure.

i.e. A wizard and 3 soldiers still standing.  Two of them are carrying treasure but there are three treasure tokens remaining.  Only two of the three remaining treasure tokens may be carried off.