THE BEST SYLVEON BUILD GUIDE - POKEMON UNITE

The introduction of Curse Incense gives Hyper Voice build a more influential third item choice. Incense now gives her even more utility to the team on top of her SpDef shredding, and makes her sustained damage hard to come back from.
The recent nerf to Spoon’s SpDef penetration ends making it now fall slightly behind Choice in output, which was already a very close race but now has a clear winner for the item slot.
Wise Glasses passive increase stacks with Calm Mind buff, which makes for repeated waves of Voice considerably chunkier.

As for Mystical Fire build, you’re looking for more sustained damage and survivability to continue your constant barrage, so the new addition of Resonant Guard aids that (with Sylveon’s surprisingly high health pool) perfectly. Muscle is there to provide noticeable chip damage in between Mystical Fire casts, and Spoon is the ideal special damage item for low-ratio/high-base damage moves like this, while also giving a bit more HP bulk that this set thrives on.

MOVESET 1:

Basically the same gameplan as Espy, push early advantage with your level 4 power spike and be a fabulous pink bully. Your dmg will rely entirely on your ability to trace your enemy’s movements with your own, and keep them in that outer cone of Voice. So practice your 1-2 step twinkle toes. Utilize Calm Mind’s movespeed buff (and X-Speed) to accomplish this daunting task.

Good thing about objectives is they don’t try to dodge your moves! So that makes Sylveon a very good Eleki/Regi/Ray burner since you will always be hitting with ALL the waves of the very painful outer Voice ring, and shredding their SpDef for allies to hit harder as well.

This SpDef shred aspect of Voice is also what makes it a nightmare for tanky frontlines, who 1) are too fat to move out of the cone and 2) depend on those stats to tank for their greedy moocher friends. Basically you yell so loud at them they descend into madness and just melt into a puddle. Combining this shred in tandem with another strong backline mage to allows them to deal almost true damage gives explosive results and proves to be very fatal for these big walls of defenders or bulky brawlers.

*Meta note*: Split jungle is making a bit of a comeback with things like Leafeon and Meowscarada being big early level-4 gank candidates, meaning Sylveon can combine with that to make a lane of their choosing victim to a double level 4 assault. Playing lane normally is still totally fine however and splitting is not strictly the only way Sylveon should be conducted.

Sylv’s Eevee form is not quite as good as Espy’s, due to Swift being a scuffed 4-hit mini gun for some weird flavor reason, and is terrible for securing. It is a decent way of ripping farm down as quickly as possible to prevent incoming enemy securers, but does take some good angling and timing due to also being body-blockable.
Getting level 4 before bees should still not be an issue if you have an Exp Share holding partner and your team isn’t griefing you.

So here’s the deal.
Mystical Fire Sylv is a VERY odd build to calc optimization for. On one hand, she wants to rushdown single targets and demand a reaction out of them with some up front damage, but on another equally important hand, she also wants to live for an obnoxious amount of time and keep pumping sustained dps into things until they keel over.

Update: Yes it still has that stupid issue of not firing to wild mons that aren’t aggroed onto you.
After the buffs there are a few matchups that MF-DK can perform a bit better into, namely mobile mages that dodge Voice reliably. However the other drawbacks outside of the 1v1 ability of the build still apply.

Mystical Fire is still 1) single target, impossible to hit groups 2) difficult to aim on the target you want 3) very low burst damage.
You can’t secure farm reliably, you can’t fight back against any attack with more than 1 enemy, you can’t burn objectives as fast, your whole existence on this set is just running people down and just being excessively violent at all times.
MF’s Special Attack reduction, mobility and Draining Kiss slow give it some nice interactions into a lot of annoying mages and certain triple-headed birds. Niche is the definition of this build.

Favourable Matchup:

These are Pokémon that our team has determined SYLVEON is strong against. SYLVEON will generally be able to shut down these opponents playstyle's or have the advantage in a one on one fight.

SNORLAX

BLASTOISE

GARDEVOIR

DODRIO

BUZZWOLE

SLOWBRO

Unfavourable Matchup:

These are Pokémon that our team has determined SYLVEON is weak against. These Pokémon will have the upper hand in a fight or be able to exploit SYLVEON's weaknesses.

MIMIKYU

DRAGAPULT

TSAREENA

ZOROARK

ABSOL