Mettaton NEO was added during Beta 4.3 as a Legendary. Previous Versions can be found here.
Overview[]
Undertale OST - Power of "NEO" Extended
0:00 - 0:06. (Note: The song shown here is how it is in UT, which is slightly slower and lower pitched than how it is in UC.)
After multiple effect changes and discussions, he was finally added to the game with the effect of dealing his ATK as DMG upon dying. As of now, this DMG is taken by all monsters, and half of this damage by the opponent (5 DMG by default).
This is particularly effective as a means to clear the entire board of enemy monsters, as well as a deterrent to cards such as Woshua, Strafe and Tsunderplane.
Combos[]
Best used in a Perseverance or Justice Deck, as they have reliable and cheap spells to deal DMG to your own NEO right after placing him down to avoid letting him be shut down by the opponent. But he's not limited to those decks, as Loox or Vulkin work just as well (though neither will survive NEO's explosion).
People using Bravery can use Overheat on their NEO to allow him to deal his ATK to all enemy monsters twice, but most of the time this is overkill and a waste of recourses due to the lack of 11+ HP monsters. (In fact, the only monsters with a base HP so high are Omega Flowey and Angel of Death, both at 11. Though, in AoD's case, if he dies from NEO's first blast, the second will kill the Lost Souls.)
If the enemy places cards like Astigmatism or Heats Flamesman, you can place down your NEO (on the required spot) in order to kill him without the need of a 2nd card.
Because of the various uses of the card, NEO can be very influential in the battlefield in terms of affecting the enemy and how they use cards as well as how you create your own deck.
Counters[]
Especially effective against Justice since it is mostly based around area damage (and placing him by himself makes Justice's passive target him, giving the opponent 1 turn to shut him down), and Determination to lessen the chances of Hyper Goner being used.
Card Skins[]
Power of NEO
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