Sol Ring

Rampant Growth

Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Command Tower

{T}: Add one mana of any color in your commander's color identity.

Farseek

Search your library for a Plains, Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle.

Ol' Buzzbark

When Ol' Buzzbark enters, roll X six-sided dice onto the battlefield from a height of at least X inches. For each die, put a number of +1/+1 counters equal to the result on each creature you control that die is touching. For each die, Ol' Buzzbark deals damage equal to the result to each creature an opponent controls that die is touching.

Reliquary Tower

You have no maximum hand size.
{T}: Add {C}.

Vexing Puzzlebox

Whenever you roll one or more dice, put a number of charge counters on Vexing Puzzlebox equal to the result.
{T}: Add one mana of any color. Roll a d20.
{T}, Remove 100 charge counters from Vexing Puzzlebox: Search your library for an artifact card, put that card onto the battlefield, then shuffle.

The Space Family Goblinson

The Space Family Goblinson has trample as long as you've rolled three or more dice this turn.
Whenever you roll a die, put a +1/+1 counter on The Space Family Goblinson.