Keep Xanos Out of the Borderwatch!
If we’re going to talk about the new cards in the new Mana Storm expansion, it would be hard to pick a more attention-getting entry than the coolest (see what I did there?) of the new leaders, Xanos the Cold Heart. One of two leaders in the set who is capable of flipping back from her upgraded side back to the basic, she is also the only leader who is never worth any victory points, and in fact likely to cost you VP if the game ends abruptly at a time you weren’t expecting. Minus 40 VP is nothing to sneeze at, so being caught with Xanos on her upgraded side at the end of the game is basically suicide. To make effective use of her, you’ll need to be very confident that the game won’t end without you getting a chance to “crystallize” her again and flip back to the starting side. If need be, you might spend your entire last turn pushing as hard as you can, just in an attempt to burn your way through your entire deck until she shows up. For this reason, even though she’s giving you an insane 3 growth on turns when she’s “melted”, you still want all the growth you can get in your deck, for cases when her upgraded side isn’t around for one reason or the other. When she is giving you all that growth, you should plan on having your entire deck in play; if you start a turn and you know she’s in your deck or discard pile somewhere, your only priority should be to get her on the table. There probably isn’t a single aspect in the entire game that’s more important than getting her “solid” again.
If using the selection method described in the rulebook for leaders and amulets, I would strongly advise against picking Xanos if you’re anything but last in the turn order; when you decide whether to pay 2 mana and flip her over, you need to be VERY clear on whether you’re going to get another turn. Keep in mind that “melting” Xanos, like flipping any other leader, counts as one of your two advancement buys for the turn; in the late game you’re likely to find that spending just 2 mana for this purpose is almost as big of a problem as the risk of being stuck with -40 VP.
One of the new vale cards, Borderwatch Bog, is similar to Xanos in how hard it bends the usual rules of play. At the end of the game, you run through the field-planting process one last time, pushing your luck as if you were taking a turn, but your only goal at this time is to try and get as many cards into your field as possible. Just as I told you to get as much growth as possible into Xanos’s deck, you’ll also want as much growth as possible in a Borderwatch Bog deck, and you might be tempted to try and use Xanos’s three growth to get that post-game Planting Phase to be as impressive as possible. This is not recommended since the final Planting Phase does not count as a turn and you won’t be able to flip her back to the starting side. If you’ve chosen Xanos as your leader, Borderwatch Bog is unlikely to be a good buy, and you should not try and involve Xanos herself in the process of exploiting the Bog’s effect.
As the only leader in the entire game who is never worth VP, Xanos starts with a disadvantage. However, the upside of three growth is huge and the trade-off is at least as big as the benefit she offers. Trying to maximize her abilities throughout the game, without catching the short-straw at the last moment is functionally a “challenge mode” for the game, letting experienced players really stretch themselves and try to make her work reliably for them – while also offering newbies at least a chance of doing explosively well, with a bit of luck.
– Article by Will Pell