From here:
https://www.reddit.com/r/FireEmblemHeroes/comments/efbuot/new_year_2019_units_lvl_40_and_1_stats/.
New Year's Anna is a red infantry archer with 40 HP, 34 Atk, 40 Spd, 16 Def, and 37 Res which gives her 167 BST and she has a speed superasset and HP and defense superflaws. Compared to her Heroes Anna since I don't think we know if it's our Anna even though NY Anna has the same side ponytail that the other Anna don't have as far as I know, -1 HP, +5 Atk, +2 Spd, -6 Def, and +9 Res. Compared to Igrene, our only other red infantry archer, -2 HP, -3 Atk, +3 Spd, -10 Def, and +13 Res. Offensively, she's a +Spd, -Atk Igrene, but overall, I guess she's kind of like a red Niles which also makes her a red Nina.
NY Anna has Fortune Bow+, Rally Def/Res+, Sabotage Atk 3, and Atk/Spd Gap 3. Fortune Bow+ has the effect of "At start of turn, if any foe's Res <= unit's Res-3 and that foe is adjacent to another foe, inflicts Def/Res-5 on that foe through its next action" which is Sabotage Def/Res 2 making it similar to Lute's refined Weirding Tome's Sabotage Spd/Res 2.
New Year's Alfonse & Sharena are a blue infantry tome duo hero with 41 HP, 38 Atk, 17 Spd, 35 Def, and 30 Res which gives them 161 BST and they have attack, speed, and defense superassets and HP and resistance superflaws. It's Alfonse's stat spread which makes sense since it's Alfonse & Sharena and not Sharena & Alfonse. That said, spring Alfonse is relatively fast.
NY Alfonse & Sharena has Embued Koma, Open the Future, Special Spiral 3, and Def/Res Oath 3 and their duo hero skill is "Grants Special cooldown count-2 to unit and infantry allies within 3 rows and 3 columns centered on unit." Embued Koma's effect are "Accelerates Special trigger (cooldown count-1). At start of combat, if Special is ready, grants Atk/Spd/Def/Res+5 during combat and foe cannot make a follow-up attack" and Open the Future is their personal skill that is part of the Glowing Ember, Bonfire tree which has a 3 cooldown and the effects of "Boosts damage by 50% of unit's Def. Restores HP = 25% of damage dealt", so Bonfire + Noontime.
The rundown is that NY Alfonse & Sharena are Ophelia with all her speed dumped into HP, Def, and Res and in return for not being able to charge their special when they're AI controlled by having mage allies on their team, they get to do even more damage and also have extra speed, defense, and resistance. They also come with Special Spiral by default. Compared to Ophelia +3 HP, +1 Atk, -16 Spd, +15 Def, and +7 Res. For AoE Special spamming, they're still going to want L&D for the visible attack stat and speed doesn't really matter when you're looking to maximize as much damage as possible.
New Year's Eir is a red flying dagger with 39 HP, 31 Atk, 36 Spd, 21 Def, and 34 Res which gives her 161 BST and she has no superassets and HP and attack superflaws, but she's the TT unit. Compared to her regular self, +4 HP, -1 Atk, -1 Spd, +7 Def, and +3 Res. So, essentially she trades some offenses and an arguably better color for bulk. HP, attack, and speed are her highest level 1 stats, so if you choose to merge her, then she will get +5 to those stats at +10.
NY Eir has Temari+, Shove, Brazen Atk/Res 3, and Spd Tactics 3. Temari+ has the effect of "At start of turn, if any foe's Res <= unit's Res-3 and that foe is adjacent to to another foe, inflicts Atk/Spd-5 on that foe through its next action" which is Sabotage Atk/Spd 2 making it similar to Lute's refined Weirding Tome's Sabotage Spd/Res 2.
New Year's Lethe is a green cavalry beast with 41 HP, 35 Atk, 41 Spd, 27 Def, and 18 Res which gives her 162 BST and she has a speed superasset and defense and resistance superflaws. Compared to her regular self, +2 Atk, +3 Spd, +1 Def, and -1 Res.
NY Lethe has Guardian Fang, Glimmer, Atk/Spd Solo 3, and Lull Spd/Def 3. Guardian Fang's effect are "Grants Spd+3. If unit's Spd > foe's Spd, deals damage = 70% of difference between stats. (Maximum bonus of +7 damage. Combos with Phantom Spd.) If unit's Spd > foe's Spd, reduces damage from attacks during combat and from area-of-effect Specials (excluding Rokkr area-of-effect Specials) by percentage = difference between stats x 4 (max 40%)." So, in addition to granting Spd+3, Guardian Fang has the speed check for damage effect that Karla's Vassal's Blade, Naesala's Raven King Beak, Nino's Giga Excalibur, and Red-Hot Ducks have and Close Call 3 minus the Hit and Run effect. With her default kit, she also has her regular self's Brazen Cat Fang's Atk/Spd Solo 3, but without the ability for it to work when adjacent to beast or dragon allies. She screams Galeforce like her regular self, but she doesn't need Desperation as much when she can reduce damage like that by having higher speed and stacking whatever skills to reduce damage. So, Galeforce, Atk/Spd Solo 3 or Spd/X Solo 3, Lull Spd/Def 3 or Atk/Spd 3, and Heavy Blade 3 as her seal.
New Year's Selkie is a colorless beast cabalry with 35 HP, 31 Atk, 39 Spd, 16 Def, and 40 Res which gives her 161 BST and she has HP and resistance superassets and a defense superflaw. Compared to her regular self, +2 Atk, +1 Spd, -3 Def, and +5 Res. As if she couldn't have lower defense. NY Selkie shares the lowest base defense for a melee unit with incidentally, another colorless beast unit, Leanne. On the other hand, she now has the highest base resistance for a cavalry unit beating Jagen by 4 points and she has the second-highest base resistance now beating regular and picnic Flora by 2 points and under winter Fae and Nagi by 1 point.
NY Snuggle Beast has New Foxkit Fang (really, that's what it's actually called), Iceberg, Distant Ward, Sabotage Spd 3, and Odd Res Wave 3. New Foxkit Fang has the effects of "Accelerates Special trigger (cooldown count-1). If unit's Res > foe's Res deals damage = 70% of difference between stats. (Maximum bonus of +7 damage. Combos with Phantom Spd.) If unit's Res > foe's Res, reduces damage from attacks during combat and from area-of-effect Specials (excluding Rokkr area-of-effect Specials) by percentage = difference between stats x 4 (max 40%)." New Foxkit Fang is similar to Foxkit Fang where with a resistance check, Selkie deals more damage and takes less damage, but in this case instead of an in-combat stat boost up to 8 points and only working against melee units, she deals at most 7 damage and reduces damage by 40% during combat against all units, but doesn't gain any speed boosts.
Distant Ward is a new A passive inheritable only to melee units of all movement types which has the effect of "If magic, staff, or dragonstone foe initiates combat, grants Atk/Res+5 to unit during combat and unit can counterattack regardless of foe's range." So, it's like a magic damage version of Distant Counter with Mirror Stance 2.5 considering it grants Atk/Res+5 instead of +4 like Mirror Stance 2 or +6 and Guard like Mirror Stance 3. Or Ostian Counter where its effect only works against magic damage units. The only issue is that since she's a colorless beast, so not an infantry unit, she can't run Null C-Disrupt, so healers are still going to be able to do their stupid things. For mages and dragons, though, it should be fine as I don't think Windsweep is that common on them and Firesweep tomes or dragonstones aren't things yet.
Those gifs are the true meaning of Christmas, my sister 
gifts.
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