If you intend to do it by the defaultroutine _mulliganRules.Add(new Tuple<string, string>("True", "card.Entity.Cost >= 0")); where 0 is the threshold mana cost. If you intend to do it with a mulligan in your data folder, there seems to be a bug in which you can't change the value for mulliganing (it is stuck on > 3). If you don't know how to do it. Open your HB folder, inside the routine there should be a defaultroutine.cs which you can edit with the notepad (I recommend using notepad++ or your beloved IDE for easier edition). To edit the mulligan.txt, you should probably use HSBtoolbox which is a wonderfull tool that can help you to create it.
As I said, HSBtoolbox don't seem to work when it comes to the discard below a certain mana value, the easiest workaround I found when using it was to just discard every card in your deck that you don't want in your opening hand and are below 4 mana cost.
That worked, thank you so much. Mostly anyway I guess...still keeping my low cost cards when I have rules set to only keep if I have a mana wyrm =/
You should to discard the low cast mana cards, make two rules for them. First a rule to discard them whatever you have in hand, and then, a rule to keep them only when you have a mana wyrm. The second rule will bypass the first one if it applies. It should work.
