Walking Sponge

{T}: Target creature loses your choice of flying, first strike, or trample until end of turn.

Rock Jockey

You can't cast Rock Jockey if you've played a land this turn.
You can't play lands if this creature was cast this turn.

Seedtime

Cast this spell only during your turn.
Take an extra turn after this one if an opponent cast a blue spell this turn.

Joven

{R}{R}{R}, {T}: Destroy target noncreature artifact.

Borborygmos and Fblthp

Whenever Borborygmos and Fblthp enters or attacks, draw a card, then you may discard any number of land cards. When you discard one or more cards this way, Borborygmos and Fblthp deals twice that much damage to target creature.
{1}{U}: Put Borborygmos and Fblthp into its owner's library third from the top.