Based on Ornamental Weapon:

Ceremonial Blade 1
Artifact- Equipment U
Equipped creature gets +1/+0 and menace.
Whenever equipped creature deals combat damage to a creature, sacrifice Ceremonial Blade.
Equip 1

Quote Originally Posted by +5 Vorpal Bunny View Post
Life-Breaking Binge XUBR
Sorcery - MR
Spend only Blue, Black and Red mana to pay for X. If X is 5 or more, this spell cannot be countered.

Target player exiles X cards from their library, than exiles X cards from their hand, than takes X damage. Damage taken this way cannot be prevented. If their hand would be emptied this way, they exile additional cards from their library equal to the difference.

'Just one... more... artic-'
- Last words of Master Mage Kath'mor
You need to specify where in the library the cards are exiled from, and the last effect has to be worded in a very particular way for the rules to actually parse it. I think the proper templating for this card (cleaning up a few other things as well) would be:
"You may spend only blue, black and/or red mana to pay X. If X is 5 or greater, this spell can't be countered.
Target player exiles a card from their hand. If they can't, exile the top card of their library. Repeat this process X-1 times. Then, they exile the top X cards of their library. Life-Breaking Binge deals X damage to them. This damage can't be prevented."

Quote Originally Posted by Kapow View Post
El Dorado
Legendary Land R
[A golden city]

~ enters the battlefield tapped.
When ~ enters the battlefield, sacrifice
any number of creatures and put the same number of wealth counters on ~.

T, sacrifice a creature: Put a wealth counter on ~.

T, remove X wealth counters from ~: Search your library for an artifact with CMC X and put it on the battlefield without paying its mana cost. Shuffle your library.
You don't need the "without paying its mana cost" when you're just slamming things onto the battlefield; you only need that if the cards are actually being cast, which in this case they're not.
A couple other suggestions that aren't about whether the card works under the rules, so feel free to take or leave them:
1. Wizards hasn't printed a land with no mana ability in quite some time, because people tend to play them wrong, for example, they'll just count the number of lands they have to determine how big they can make an X spell, etc. and forget that one doesn't produce mana. It also makes it harder for opponents sitting across the table to figure out how much mana you have potentially available. That's why most nonbasics at least have "Tap: add C."
2. The last ability is extremely powerful in any environment with artifacts that have CMC 0. I suggest adding the rider "X can't be zero" so that players have to actually use some counters to use the card.