Equipped creature gets +4/+4 and has protection from colorless and from multicolor. This effect doesn't remove Sword of Existence and Nothingness
Whenever equipped creature deals combat damage to a player, exile target permanent, then add at the beginning of your next main phase.
Equip
The definitive sword of X and Y. With the adding of protection of colorless, we now have a collection of swords that protect the creature from every possible source, at least when it comes to damage and targeting, and the adding of multicolor seems a nice way to make contrast and to have niche but overall cool protections if you see the card in the big picture. Somehow flavorful too, colorless gives a nice idea of void and nothing and is represented also by the ability to exile and annichilate into nothingness any kind of thing. On the other hand, multicolor gives the idea of the diversity of life and the "add WUBRG" represent the source of creation of new things (the spells you will cast from hand, presumably).
Costs and stats are all doubled compared to the regular Sword of X and Y, because this power level would be certaintly absurd at that mana cost, and also, I like the idea that this sword is like the "king" the rule all the others, made it legendary not only for power level balance, but also to allow a few tricks, especially in EDH, as being able to be tutored by Sisay, Weatherlight Captain for example. Obviously this is a "timmy" sword not designed or pushed for competitive play, but splashy enough to be exciting and powerul in the right casual environment. (also, it's actually still pretty pushed if you compare it with other equipments with similar costs and effects like the Argentum Armor.)
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