You dont want to put this on your battlefield if youre already behind in lands and ramp because those are minimal costs to pay for your opponents to deny you known card advantage
When he shows up, he a 4/3 with a powerful build-around ability: whenever you cast a spell, you create a 1/1 colorless spirit creature token that can't block or be blocked by non-spirit creatures
My opinion on why Standard has been stale over the last few years is because there have been a small number of cards that have been much better than the rest of the card pool, which means you had to play them
However, like Necropotence, it was eventually pushed to such a degenerate place that fewer and fewer games were actually interesting when it was on the table
Importantly, this ability makes it around those pesky token decks as it forces opponents to sacrifice non-token creatures
The Response side as emergency removal is fine, as well