Planeswalkers have extremely useful abilities that fit well into any control decks.

At the same time, they are very vulnerable to burn, evasive creatures and some of them have too high a casting cost. What if any sort of impact do you expect they will have on legacy?

Garruk seems like it could see play, perhaps in UG Threshold. I say this because it's the one Planeswalkers that can generate threats. At worst, it's a 3/3 for 4 mana AFTER your opponent used a burn spell to kill the planeswalker itself. That's not too bad.

The blue one is similar to Ophidian and may see some play.

The others seem like their casting cost is too high though. Even though Lilena Vess has some great abilities.

We will see five more each set. Do you think this could eventually make burn and evasive creatures a lot more popular?