If a planeswalker than has been turned into a creature (not a planeswalker that turns itself into a creature with "prevent all damage" like Gideon) takes Infect damage, what happens?
I know that Infect damage is applied as -1/-1 counters, and I know that the planeswalker will have both damaged marked on it, as well as have it's loyalty reduced, but what I'm unsure of is if the -1/-1 counters further reduce the loyalty or if they only impact the power / toughness.
As a follow-on, do the -1/-1 counters stay on the planeswalker when it is no longer a creature? And if so, could this be used to prevent a Gideon from using it's "become a creature" ability (or at least kill it if it does)?