well, its soo weak, it would fall to any slightly hard CC. i guess slapping a condition that automatically destroys the card whenever it's targeted resembles some of MTG's illusion creature (even though its a spirit in MTG) :if creature is target of spell or ability, sacrifice that creature.
I know what you're thinking. Yes, it is weak. Yes, it would fall for most CC relatively quickly. And yes, it reminds me of M:tG.
Because I've played it.
I've actually played Magic since Unlimited. And the last time I've seriously played was Academy (there was no set called this, it's the name of a card). Actually, Academy was so powerful they didn't "nerf" it -- they banned it*. From tournament play. And it's only a "land" -- or equivalent to Pillars or Towers in this game. At the time, it was a $20 card -- you needed four and a full time job to build a 60 card deck.
I tend to take a really conservative approach to cards -- don't take it personally. Based on my experience with collectible card games, it is much, much easier on the community to "buff" a card than it is to "nerf" it.
Why take a hard stance on Will-o'-the-Wisp? you may ask...
It's "Underworld Dreams" on a stick. In M:tG, it's restricted (meaning you can only have one). Here you can have six. With Fractal, you can have an army. And with Eclipse in play, they can start multi-tasking.
Sure, this game may not have a "Brain Geyser", "Stroke of Genius" or "Wheel of Fortune" (or worse, "Ancestral Recall" or "Time Twister")...at least not yet. At any rate, the card synergizes with a few cards already and it has a powerful ability that should not be overlooked.
-Heart