In comparison to the regular longsword, the imbued longsword has a +4 increased stab and +6 slash bonus, and a +25% accuracy to the special attack. In addition, the special attack is one tick faster (2.4 seconds instead of 3.0 seconds).
In addition, it can only be used within Daimon's Crater, Castle Wars, Clan Wars, and Soul Wars; attempting to attack anything outside the listed areas will result in the player being interrupted from doing so.
The dragon longsword (bh) has a special attack called Cleave, which raises both the player's maximum hit and accuracy by 25%, as well as temporarily increasing the attack speed of the weapon by one tick (from 3.0 seconds to 2.4 seconds) for one hit after performing the special attack; potentially allowing the player to use multiple special attacks in quicker succession than the regular dragon longsword. This consumes 25% of the player's special attack energy.
The accuracy roll for Cleave is based on the attack bonus of the player's currently select style, which is rolled against an opponent's slash defence.[1]
^Jagex. Mod Ash's Twitter account. 17 July 2018. Archived from the original on 24 December 2022. Mod Ash: "[Hey, do you happen to know whether the dragon long uses your current combat style for its spec or is just always slash? (...)] It uses your current style but rolls against the NPC's slash defence."