Hello Pojo, Last month, I shacked up with a cougar in the west, and right now I'm moving from NJ to Florida.  I've been busy.  So has the Kozmo support, Christian Moss tells me.  If you thought Kozmos were powerful enough, their flawless engine has even more support to bolster it.  Unfortunately, Lightsword is not one of their better ones.
 
Here's why.  THE MONSTER CANNOT ATTACK DIRECTLY WITH THE EFFECT (ONLY ON MONSTERS)
 
Killing a monster in battle to make it easier for another monster to attack is still decent.  The piercing effect will also punish.  Since you can add it to your hand on destruction, it lacks the -1 risk most equip cards pose.  Plus, it can't be disrupted with an MST and the like.  It also might make the opponent waste removal on a monster they wouldn't normally use it on. 
 
It might work as tech for side deck against certain matchups, but since it has zero OTK potential and it doesn't grant you any card advantage, I would suggest running no more than 1 copy if you insist on running it.
 
2/5

Apparently it's Kozmo week around here.  As a general rule of thumb, to which I'm sure most players are aware, equip Magic cards aren't very good, or reliable.  I mean yea, we used Axe of Despair and United We Stand way back when, and even Mage Power, but that was a completely different era of play, with far less mechanics and tools at our disposal.  But as far as an Equip goes, Kozmo Lightsword is pretty good.  For starters, you get 500 attack and defense for the equipped Monster.  Which is a formidable enough increase.  Secondly, the equipped Monster can attack two Monsters in a Battle Phase.  Plus, on top of all that, it grants the equipped Monster piercing Damage, when applicable.  This card can only be equipped to a Psychic Kozmo Monster, just remember that, and can even be recycled to the Hand for 800 Lifepoints.  (I don't see that happening very often) but this Equip gives you three effects, and even if you only get it for a turn or two, it should play well in your favor.

Rating:  3.5/5

Welcome to Kozmo week! Today we start with some interesting support for a very expensive deck. Kozmo Lightsword is an Equip Spell Card. Fortunately, it is costless and grants excellent bonuses. Unfortunately, Even within the archetype, it only equips to Psychic-type Kozmo monsters. It gives that monster 500 Atk and Def, the ability to attack twice on opponent's monsters, and piercing if it attacks Defense Position monsters. I get that you can search this from the Deck if Kozmotown is destroyed, but more than likely, you're going to be able to equip, attack, inflict damage, and then start Special Summoning the ships. Then this card hits the Graveyard and the second effect kicks in. If you pay 800 Life Points, you can add Kozmo Lightsword back to your hand from the grave. However, it's not like you can activate it during the Battle Phase. If you could, this would receive a higher score. Since you can't we have the usual rule "most equips are bad."
 
Score: 2/5
Art: 5/5
-WarlockBlitz

Well, this is going to be a fun week. I've said before that I'm really intrigued by this Kozmo set, mostly because of the “Wizard of Oz” theme, not so much the “Star Wars” one. Don't get me wrong, Star Wars is a great franchise, but something about seeing Dorothy and crew with a sci-fi twist really speaks to my inner child. But now I'm getting off track.

Before I get into the card, let me point something out: Usually I rate cards by their compatability to decks in general- Dragon, Swarm, Firefist, etc. But since this is Kozmo week, I'll be giving these cards rather high scores because they are very deck specific. I do not recommend you splashing them with other card themes, because that could spell trouble for you. With that in mind, on to the actual review!

Kozmo Lightsaber- I mean Lightsword- is a decent Equip card, especially for its theme. So far, the Kozmo Psychics I've seen look weak and could use a power-up boost. This card gives them that, and more: double-attack, “peircing” (AKA, battle damage to DEF position monsters), and it can call itself back with the cost of 800 LP. Sort of like how a Jedi uses the Force to call back his sword after it's been knocked out of his hand. Definitely run at least two of these in a Kozmo deck. You'll need it to keep your Psychics from getting run down by bigger baddies.

Final Score: 4/5