I tried to use Shifting Woodland’s ability to turn into a planeswalker. Having never played with the card before, I thought intuitively that I could do this. I was dismayed to learn after the game that doing so would have the shifting woodlands transform into a planeswalker with 0 loyalty counters, sacrificing it as a state based action.

The way this appears for the user is as a bug, without any animation or explanation. You select a planeswalker in your graveyard and then the land is just immeadiately sacrificed and the game moves on.

There really should be one of those “Do you really want to do that” prompts when you select a planeswalker using this land’s ability. Otherwise, there should be some way for the user to see what happened to the planeswalker/land - ie, that you messed up. More feedback for the user would make this interaction more enjoyable, and allow for players unfamiliar with this interaction make better decisions.