From Murako and the official site:http://pad.gungho.jp/member/seasonal/xmas/161215_xmas.html
* Christmas dungeon and REM returns to JP for a week from 12/19 to 12/25
* 1 Free rank 50 roll
* Only Holy Night Red Dragon Caller, Sonia will be available in the MP Shop, not the other 8*s.
Ult Xmas Haku
(changes to Fire main attribute)
God / Dragon
Same active as normal version: Changes board into Fire, Water, Dark orbs.
LS: 3.5x ATK when attacking with 3 of Fire, Water, Dark or Heal orbs. 2x ATK when matching 5 connected 1 enhanced orbs.
Ult Xmas Liu Bei
Dragon / Attacker
Same active as normal version: Changes Dark and Heal orbs into Fire. Recovers 30% of max HP
LS: Increases all Attacker stats by a little. 3x ATK with 2 Fire combos, 6x ATK with 3 or more Fire combos.
God / Balanced
Same active as normal version: 1.5x Wood attribute ATK for 3 turns. 1 turn haste.
LS: 3x ATK and a HP boost to Wood cards.
Healer / Devil
Active: Changes Wood to Fire orbs
LS: 1.5x HP/RCV and 2x ATK to Healer type cards.
Pollux & Castor
Machine / God
Active: Changes leftmost column into Light orbs and rightmost column into Dark orbs. 1 turn haste.
LS: An ATK/RCV boost to God and Machine type cards. 5x ATK when matching 5 connected 1 enhanced orbs.
Devil / God
Active: Randomly spawns 3 Fire and 3 Heal orbs. 2 turns bind recovery.
LS: 2x ATK to God and Devil type cards after using a skill. 6x ATK and 35% shield with cross Heal.
* Xmas Sakuya LS buffed to 5x ATK when attacking with Fire, Water, Wood, Light orbs (up from 4.5x). 1.5x HP/ATK to Healer type cards.
* +300 HP
* +700 HP to Red Kali
* Selling price increased to 25,000 MP (up from 15,000)