The first tools you need are: an axe (chopping trees), a knife or mace to fight (against the dwarves is good the torch- they are afraid of fire), a hammer for building (if you hold it in hand, middle button destroys a target structure) and a hoe to level and raise the terrain (you can build dirt walls, which are indestructable with attack). The trench can only be made after killing Eikthyr and making a pickaxe. I recommend the knife for combat due to its secondary attack - a jump to a target from a greater distance - very good ability and for troll killing is must to have. Later, when you have enough material, a buckler must be made to repel the attacks.