Throne of Geth

{T}, Sacrifice an artifact: Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Omnath, Locus of All

If you would lose unspent mana, that mana becomes black instead.
At the beginning of your first main phase, look at the top card of your library. You may reveal that card if it has three or more colored mana symbols in its mana cost. If you do, add three mana in any combination of its colors and put it into your hand. If you don't reveal it, put it into your hand.

Helm of the Host

At the beginning of combat on your turn, create a token that's a copy of equipped creature, except the token isn't legendary. That token gains haste.
Equip {5}

Phyrexian Tyranny

Whenever a player draws a card, that player loses 2 life unless they pay {2}.