Blade of the Bloodchief - 1
Artifact - Equipment Rare
Whenever a creature is put into a graveyard from the battlefield, put a +1/+1 counter on equipped creature. If equipped creature is a Vampire, put two +1/+1 counters on it instead.
Equip 1

For the 2 mana it costs to get this to do anything, you're better off playing a 2 drop creature, like Putrid Leech. Might not be AWFUL in a Vampire deck, but seems pretty bad.

Eldrazi Monument - 5
Artifact Mythic Rare
Creatures you control get +1/+1, have flying, and are indestructible.
At the beginning of your upkeep, sacrifice a creature. If you can't, sacrifice Eldrazi Monument.

Making a horde of tokens evasive, fat, and indestructible has never been a bad thing, but turn 5 might be better spent making 6 1/1 soldiers or something. It has potential, but is probably a safe bet to stay cheap. Grab a few early if you have faith in token decks again.

Eternity Vessel - 6
Artifact Mythic Rare
Eternity Vessel enters the battlefield with X charge counters on it, where X is your life total.
Landfall - Whenever a land enters the battlefield under your control, you may have your life total become equal to the number of charge counters on Eternity Vessel.
There's enough artifact hate available to make this slightly less scary, but if a control deck can resolve one with 10 life or more, the game's going to take a while. Setting a life total is considered gaining or losing life, so those triggers will apply. It's too fragile for tournament play, but EDH players are going to have an absolute BALL with this.

Artifact - Equipment Rare
Equipped creature has double strike.
Whenever equipped creature attacks, you may have target creature block it this turn if able.
Equip 4

That's an AWFUL lot of mana just to give double strike. It'll probably tear it up in Limited, but as far as constructed is concerned, ignore it.