Believe it or not, lightsabers are actually kind of heavy.
Lightsabers consisted of a plasma blade, powered by a Kyber crystal, that was emitted from a usually metal hilt – comparable to a heavy longsword hilt.
A two-handed sword from medieval times could weigh anywhere between 5–10 pounds (in between 3–7 pounds for most swords) depending on the style/type.
You’d think the blade is essentially weightless because of the plasma blade, but anyone familiar with fencing/swordplay knows that the weight of the handle and blade, and thus the overall balance of the weapon, is critically important while fighting.
A sword that is too blade-heavy is unwieldy; it is difficult to start, stop, and change the path of the blade as it’s swung, which is vital to outmaneuvering your opponent in a duel.
Conversely, a sword with too light of a blade (equivalently, too heavy a hilt) is too easy to swing around. it’s hard to “feel” where the blade is, and thus to make the minute changes needed to block a blow or land one.
Therefore, Kylo’s blade presumably weighs between 3–7 pounds and is “perfectly” balanced… As all things should be – oops, wrong universe.
Why is he swinging it like it’s really heavy?
- Kylo’s fighting style is aggressive & not pretty. He is using a sloppy, unrefined version of Form 1 Shii-Cho.
- As you swing a Jedi-blade, you should avoid swinging close to your body as it can cut through blast doors as well as flesh – which we’ve seen a time or two. His saber also has the two lateral vents (crossguards) to prevent the unstable, cracked Kyber crystal from overloading. Therefore, he must do wider, heavier swings to avoid maiming himself.
Kylo likes to use powerful, reckless attacks to physically dominate his opponents. He’s not interested in outlasting his opponent and just pursues a relentless forward motion when fighting.
The reason it looks like it’s heavy is that it most likely is…
Try walking around a forest, with a longsword in hand, aggressively attacking any enemy within swinging distance.
You’ll get winded too.