In fact, I think it's more than a little insane, because if one had no removal in hand at the time I'd probably just be scooping. In any case, it's all good fun and would make for a good, maniacal laugh when pulled off.
|Giant Insect Rhino Fungus|
First turn, we play a Forest and then slap down an Arbor Elf.
Turn 2 throw down our second land, then tap both for a Farseek.
Turn 3 we play another land and then place our Giant Insect Rhino Fungus, then we tap Arbor Elf to untap a Forest, then retap afforementioned Forest and throw Rancor onto the Deadbridge.
Finally, at turn 4 we play another land, making for 5 in total, then play a Corpsejack Menace, use the 5th land for a Bond Beetle and putting the counters onto the Goliath, then we swing with the Goliath, pray they attempt to lower the damage coming from the currently 9/7 Trampler running at them and, if they do, we slap a Hunger of the Howlpack right onto our already-massive creature after untapping a Forest with our Arbor Elf for a total of 6 +1/+1 counters placed on him.
So there you go, a 15/13 creature with trample on turn 4.
Viable? Well, I don't really know, but against anything not black or blue, I'd say so. Definitely kitchen table friendly in the least.
Fun? Oh god yes!
As long as your opponent doesn't have any cheap removal you'll be set and it's pretty much game over right there. If they do, well, at least your Rancor comes straight back to your hand, your Corpsejack is down and you've got a bunch more mana than you should, plus a couple of chump blockers until you can more buffs and bodies down.