The game can be easy to beat if you take the time to level up your party and retreat from overwhelming danger if necessary. The difficulty of storyline missions raises quite sharply; you are expected to practice and enhance your stats by playing the secondary missions inbetween.
General mission tactics Edit
Don't forget: There are teleporters on each level of a mission, and you may also have a teleport spell. If the going gets tough, you can transport back to the headquarters, heal and re-equip your party and then continue the mission.
Battle tactics Edit
Don't be a martyr. If your party is about to become an ex-party, run away (most monsters are slower than you) and take some time to heal up. Notice that monsters loiter around, so it is a good idea to have a closed door sitting between you and the enemy mob.
If you have ranged weapons and the enemy has not, build a barricade from pieces of furniture and shoot arrows over them.
Monsters don't detect traps. Just lure one in and enjoy the problem solving itself.
The oldest trick from the book works in S.C.O.U.R.G.E. too: If you are well armored, stand in a doorway and let them come one by one.