Let me extend this a bit:

https://apps.magicjudges.org/forum/topic/4201/

Say I have a lot of vanilla creatures and an opponent's Kopala, Warden of Waves in the target pool for Goblin Test Pilot. Several scenarios:

0) I happen to target Kopala, having a lot of lands untapped. As per my understanding of the original post, I need to pay or get DQed.

1) What if I have all lands tapped, and therefore no mana available?

2) Same as 1), but I also have 2 Simian Spirit Guide in my hand which my opponent does not know about.

3) Same as 2), but my opponent knows that I have those because of a Peek.

Except for 0), I am quite lost. Can anyone help me?

Policy is not designed to cover every corner case. It's not difficult to come up with scenarios like this one that don't have a resolution under current policy. If Goblin Test Pilot ever starts seeing play in any format whatsoever, I'm sure we'll get an update. Until then, it's not really meaningful to ask.

Karel, I'll reiterate what I said in that original post, five years ago (nothing's changed, in this regard):
If you intentionally break rules to gain an advantage, you're Cheating. And, back then - and now - I'm of the belief that activating an ability with the intention to “fail” while paying for it if it doesn't work out the way you want, is close enough to assess Cheating.

Again, as Isaac said, policy doesn't stretch into all the deep, dark corners of our imagination. It can't, because there's a lot of different cards (what is it now, 18,000 or so?), and the various permutations of all those extensions to the Comprehensive Rules, Magic Tournament Rules, etc., simply can't be anticipated.

Of course, the snarky reply that comes to mind is “the very next time this actually happens, call me” - but (a) it won't, and (b) no, you don't have my number, huh? :)

d:^D