Buy RS3 Rune longsword
The rune longsword is a tier 50 melee weapon in RuneScape 3. It goes in the main-hand slot and uses the slash style. You need level 50 Attack to wield it. The sword has 850 accuracy and 612.5 ability damage, which makes it a solid pick for mid-level combat training and quests.
This weapon can also be upgraded at a forge and anvil with rune bars. Each upgrade raises its tier, accuracy, and damage. At the top level, the rune longsword + 3 reaches tier 53 with 928 accuracy and 649.3 ability damage, and it still only needs level 50 Attack to use.
Players who train Invention can disassemble the sword for materials. It gives base parts, blade parts, and metallic parts most of the time, with a small chance for sharp and dextrous components. It is also very light, so it will not slow you down.
Before the Evolution of Combat update, this sword was seen as the second-best non-degrading free-to-play weapon, just behind the rune scimitar. It remains a classic and useful blade for mid-level melee fighters.