Chandra, Flamecaller is a rumored new Planeswalker from Oath of the Gatewatch.
“What scenario is this card NOT good?”
There is already precedent for a six mana Planeswalker with the ability to sweep the board (and stick around) in Elspeth, Sun’s Champion (Patrick even won a Pro Tour using that Planeswalker); Chandra fits that minimum bill.
Let’s look at Chandra’s abilities… Backwards:
[-x] At her absolute worst, Chandra’s [-x] ability is a “Savage Twister” for four damage at 4RR… Which combined with any amount of versatility at least gets her in the conversation. If you have four toughness creatures and can just “Slagstorm” leaving Chandra, Flamecaller on the battlefield that can help create a massive advantage on the board.
 Chandra’s “zero” ability is just card advantage. If you have no cards in hand, this  gives you a net one card… And if you have any number of cards in hand, the ability becomes extraordinarily powerful. Once you have any number of cards in hand you can start to fuel Delve spells like Murderous Cut, set up creatures like Deathmist Raptor and Den Protector, or enable completely new (or rather, rediscovered) color combinations in Standard.
[+1] Mike initially thought this was the least interesting ability, but Patrick predicts that the “attack for six with haste” ability is the money ability on Chandra, Flamecaller. We were already (probably) happy to play Chandra for her sweep and card advantage abilities… But she can quickly close out a game, too!
Patrick and Michael believe that Chandra, Flamecaller will be an exciting and highly played new Planeswalker via Oath of the Gatewatch… But take a good (and pretty entertaining and analytical) hour to get there.
The cool thing about Chandra is that she is such a powerful card that we will see her both incorporated in existing archetypes and as the centerpiece of all new decks! Find out which in “Chandra, Flamecaller Analysis”.
Top Level Podcast also jams on Kalitas, Traitor of Ghet
“This card is bananas. This card is going to rupture my heart.”
You might be surprised as to what cards Patrick compares this one to…
… Or what weird angle (and what abilities) Mike concentrates on with his initial analysis.
All this and many new deck-inclusion, brewing, and crafting ideas in “Chandra, Flamecaller Analysis”