You gain a +1 bonus to attack and damage rolls made with this magic weapon. When you hit a giant with it, the giant takes an extra 2d6 damage of the weapon’s type and must succeed on a DC 15 Strength saving throw or fall prone. For the purpose of this weapon, “giant” refers to any creature with the giant type, including ettins and trolls.
RollQuest ships the D&D 2014 SRD as a content pack, on a 5e character sheet that does the maths - roll from the sheet and let the numbers work themselves out. Free to start.