Hmmmm. So it's either Impulse or Implode. 3 mana is far too cheap for a cantrip LD spell, but if the card you draw off the cantrip is forced to be a land? I'm pretty sure Wizards would cost this at 4 mana, but if it's only being played in this set then it probably won't break anything down at 3.

Well, it's a Sinkhole variant. I could see my way to upcosting it though.

Jesus, that's so much LD

Well yes. It's going to be a balancing act.

Note that much of it will be land-sacrifice; not outright destory opponents land.

If you're going to have an LD theme, and you want to keep things fun, then I recommend using some of those LD slots for creatures that give the option to the opponent of whether or not they sacrifice a land. Something like this:

3RR
Creature - Ogre
When ~ enters the battlefield, target opponent may sacrifice a land. If they do not, put three +1/+1 counters on ~.
3/3

That makes it so players are being pinched by an LD theme, but they can still play the game. Nothing is so frustrating as being forced to play a game with only three lands ever.

"opponent sacrifices a land" is also preferable to "destroy target land" because it doesn't punish a color skewed start. Targeted LD makes multicolor play much weaker.