You gain a +1 bonus to attack rolls and damage rolls made with this magic weapon.
When you hit a Giant with this weapon, the Giant takes an extra 2d6 damage of the weapon’s type and must succeed on a DC 15 Strength saving throw or have the Prone condition.
RollQuest summary +1. On a hit vs a Giant: +2d6 damage of the weapon's type, and DC 15 STR save or Prone.
RollQuest ships the D&D 2024 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.