IN RTL:

When rolling an attack with a monster, the OL rolls surges. He needs 2 surges to get one threat. Do surges roll over? For example the OL rolled one surge. What can be done with this surge? Is it lost as you need 2 for a threat? Can the OL use surges to upgrade range and damage like Players can, and if so, at what cost?

During an encounter, a master has the reinforce ability. Lets say its to summon skeletons for 2 threat each. If all the white skeleton figures are in play, can the masters till summon more? Can I substitue master skellys as stand ins for whites? What if all those are out too? Can i start using beatsment for white skellys?

Bravo McWilley said:

1) Surges can not be saved for later use. If you only roll one during an attack, and on the next attack roll another you don't get a threat. You need to roll two in one attack to get the threat.

2) The OL can't use surges to upgrade range or damage.

There are naturally two exceptions to this I can think of offhand: One is a Bash attack made by a Troll. The OL can use surges on that to gain damage and pierce. The second is monsters with Dark Prayer generate 1 Threat for each surge the OL rolls PLUS get +1 damage and +1 range for each surge.

As for all dungeons and quests, you are limited to the figures that came with the game except where you are told you can substitute. So no using master skeletons for regulars and certainly no using beastmen as skeletons. If you run out, you just can't reinforce more of them.