Its seems they are giving everyone the chance to play different elements without depending of Sol or Amaterasu mainly, and they gave it for free with the xmas event, seems a good choice for those who doesnt want to spend money, i know most ppl here plays in nutaku but i wanted to tell the good news, and they keep giving every element the same chance to be "usable" with every role covered.
Her name seems to be Greila (SR)
Her skills
All party members heal with a base power of 800 (1000 when powered up)
An attack up for all party members (A frame, 30%-35% when powered up)
One enemy attack down (small) and removes attack up buffs.
And the support skill heals a random party member for a power of 300 every time she uses an skill.