User blog:RealArity/UoC 2.0: In my opinion

Gumi has blessed screwed us over with UoC (unit of choice) once before and is bringing it back again. For that matter, I wouldn't expect them to fail this time, as it appears they will use a system which delivers the UoC almost instantly. As a result, a ton of hype is expected, as well as a ton of questions as to what should be the unit of choice. Fear not, as I will try to help with that by offering my opinions.

Before I begin...
There is no definitive answer for the right UoC! You are free to choose any unit you want and not follow my recommendations. This is purely based on my opinion of the units, and why I recommend them may not be agreeable with your opinion. Please do not ask questions like "why is my not a good UoC go die you f**ing pleb" or leave snarky comments such as "zoom zooom frontier only frontier avant is trash kek" which do not help other people who are viewing this blog post and the comments beneath it.

Unit Roles
'''WARNING! Skip this section if you already know what type of unit you want.''' With all that said, I should have covered the most important (and some less important) buffs. Weigh your options wisely, as you only have one choice and you may not be able to fill all roles at once.
 * Crit buffer - Boosts crit damage. Useful for Medal Rush OTK, speed killing Raid bosses and generally pissing off your raid partners by not targeting a part (don't be this asshole). Some Raid parts and Trial bosses may be Crit resistant or even Crit immune. Also helps a lot in FH Middle/End and FG1 farming.
 * Crit rate buffer - Boosts crit rate. Generally your crit buffer should boost this. Doesn't have much effect against Crit resistant bosses, and has no effect on Crit immune bosses such as Elgif Lv. 7.
 * Spark buffer - Boosts Spark damage. Probably the most reliable form of damage augmentation, and while Spark damage resistant bosses exist, you will be able to squeeze some extra damage out of it. In general, all forms of damage augmentation help with FH and FG farming.
 * Stat buffer - Boosts any of the 4 measurable stats (HP, Atk, Def, Rec). HP buffers are pretty rare, while various units may specialize in buffing one or two stats. Tribuffers are units which boost Atk, Def and Rec. HP buffs are permanent until end of battle, and in Trials, HP buffs are passed on to Squad 2 if Squad 1 dies.
 * Stat converter - Converts from one stat to another. Currently, only Atk and Def can be boosted by conversions from other stats. This is useful in RC6, when you may need to beef up your defence further.
 * Mitigator - Reduces damage, typically by 50%. By far the most important unit type for any squad, you can't clear hard content without this. On UBB, mitigation typically reaches 75%, with duration dependent on unit.
 * Status inflictor - Inflicts one of the various status ailments. Paralysis is useful in some maps where mobs/bosses can be nullified by paralyzing them, and is generally the best way to lock down opponents in Arena. Injury reduces the foe's damage, and is good for checking an offensive threat. Curse locks down some Raid parts in RC6, helping to avoid a massive nuke. Poison is the only way to kill Grand Jelly outsie of OTK.
 * Element buffer - Gives type to attack. There are bonus points in FH for stronger element, and they give an overall boost to damage against weak types, so element buffs help to boost FH scores by a great margin and FG scores to some extent. Element buffs also help in speeding up kills as a result.
 * BC droprate buffer - Boosts BC drop rate. Generally the main way to fill BB gauge, but BC resistance will put a dent in BB gauge sustain.
 * BC fillrate buffer - Boosts BC fill rate. Similar to the above buff, very useful in unresisted content, but BC resistance hurts this.
 * BC turnfill & BC/turn buffer - Boosts BB gauge after each turn, over a few turns (latter buff). Helps to fill the BB gauge, without the need for BC. By reducing reliance on BC, you can survive BC-starved content with a full BB gauge at least each turn.
 * BB on Spark/Attack/Attacked/Crit - Boost BB gauge when sparking/attacking/attacked/crit procs. BB on Spark is ultra reliable, especially with a Spark blanket (explained later). BB on attack is more often an effect on BB/SBB, causing a single unit to reap the effects selfishly. BB on attacked is another reliable way to refill BB gauges, especially against bosses with tons of AoE (area-of-effect) attacks and 5-mob stages. BB on crit is not as reliable and pretty much useless against Crit immune bosses. Generally, BB on Spark and BB on attacked are the most important buffs, filling the BB gauge in BC-starved content.
 * Hit Count buff - Increases normal hits. Useful for arena OTK, and also helps with potent normal attack strategies for bursting down some bosses such as Elgif Lv. 7. You may need units with Hit Count LS and ES in Challenge Arena to dispose of threats like Hadaron quickly.
 * Critical Spark buffer - Gives 50% boost to Spark damage. Rare and seldom seen buff that can is effectively a Spark with extra damage, giving rise to potentially higher FH/FG scores. Not a very necessary buff but a very useful one.
 * Elemental mitigator - Reduces damage from particular element. Not very useful most of the time since most of these buffs have a low percentage and mitigation stacks multiplicatively.
 * Status cleanser - Removes status ailments. Useful in all sorts of content, especially in RC6 and Trials, where mobs and bosses like to inflict Curse, Paralysis, Weakness etc. Eve in Lin's GQ is notorious for buff wiping and inflicting 100% Paralysis. TIP: Equip your status cleanser with a status negate sphere, unless ES negates status ailments!
 * Status negator - Prevents status ailments. If you have this on your leader, it's useful; otherwise, a status cleanser will do just fine, and is better than a status negator in instances when LS can be wiped.
 * Atk-down inflictor - Inflicts Atk-down debuff on enemy. Useful for survivability and when stacked with mitigation + Def buff + Def convert + injury, helps to check offensive threats and possibly even neutralize them.
 * Angel Idol unit - Unit which gains self Angel Idol buff. Probably the second-best unit type for Arena and Challenge Arena, such units can survive a Hadaron lead and retaliate with a shot of their own. Also useful for escaping Raid bosses such as Shusui after triggering a nuke, when you run out of smoke bombs.
 * Spark blanket - High hit count unit with impressive hit distribution. These units are great for maximizing Spark damage and are great for Medal Rush and FH/FG.
 * Heal over Time (HoT) unit - gradually restores HP. HoT is useful for countering Damage over Time (DoT) inflicted by Raid bosses such as Shusui and some Trial bosses such as Paris. Usually, if you don't have such a buff, you could get killed after factoring DoT.
 * Burst Healer - restores HP in one go. Useful for countering damage reflect from other units and also in general good for survival. For the first case, you may want a non-attacking burst healer such as Charla (on BB) as the healer would stll take damage reflect and could die the next turn.

20 most useful units, in my opinion (not in order):
Trust me, I would have loved to put more units in here, but they were either too niche or outclassed by other units (in my opinon). Or perhaps there just wasn't enough space for them up there. Consider these units too: Wow, this sure turned into an almost all-units analysis. If I had to rank them all by content needs, here are the top 5:
 * Haile - tribuff + BB mod + best BC management; usable in virtually all content; great for CA due to her BC management and all stats LS
 * Avant - 2nd best LS for damage augmentation, but still a better choice than Nyami for FH due to his insane UBB
 * Allanon - next best all Element buffer after Zeruiah; perpetually designed to outclass Shida. Also has Max HP buff, BC turnfill, elemental mitigation on BB, making him great at supporting the squad
 * Tridon - only unit with a Shield and is extremely bulky. Almost surefire pick for hard content
 * Laberd - best defensive mitigator with BC on attacked, also has great defensive LS and inflicts Atk down on SBB
 * Lafiel - top-tier defensive LS, single-handedly manages BB gauges with her SBB with BC on Spark and BC on attacked
 * Gildorf - explosive nuker with a single-target (ST) and AoE attack all in one; good for bursting Raid parts. Single-hit, so sparking puts his damage in the realm of gods
 * Isterio - great at inflicting ailments, notably for beating Grahdens' and Owen's trial. Also comes with a Max HP buff for increased survivability
 * Nyami - best LS for damage augmentation, but with a weaker UBB than Avant, becomes second to him; generally overrated compared to Avant due to hype generated by her SBB name and her appearance, but don't let this comment fool you as she's almost best at what she does. Also has gradual BB mod increase on SBB
 * Rosetta - top-tier Spark buffs, but may be outclassed by Omni Evo Eze on release as her 7* may be released later. Still has a unique Spark restores HP buff on SBB which is valuable in high-level raids.
 * Charla - non-attacking but carries the best damage augmentation buffs. Useful in all hard contents and is instrumental in the "Guard Frontier" strategy in FH Middle/End
 * Krantz - quality mitigator with decently cheap SBB cost. Cures ailments on BB and burst heals on SBB, but you'll want to bring another status remover instead
 * Korzan - best crit lead for high-level raids, damage mod increases as HP goes down. Great survivability due to Max HP buff. Don't be a dick and bring a crit lead to RC5 or Amu Yunos
 * Chrome - highly effective Spark leader with BC on Spark on LS and SBB, albeit at a percentage
 * Rouche - single-hit SBB with gradual BB mod increase, fantastic Crit and Crit rate buffer. My sleeper pick for CA has he can bypass Angel Idols with his crit-boosted SBB
 * Piany - generally good LS for Trials, recovers HP and BB gauge on Spark + negate status ailments on LS. Strong Atk convert boosted by Rec buff on BB. SBB adds BC on attacked, making her a fantastic lead for Raids and Trials.
 * Phoenix - great defensive LS with HC droprate buff and stat boosts. Also Angel Idol unit who gives Angel Idol (10%) on BB, and Max HP buff on UBB, making him pretty valuable for Trials
 * Darvanshel - unique, strong defensive LS which negates ignore Def, meaning new players who get him can dominate some Trials. Over a month away from him though
 * Elza - viable Spark buffer as a sub, LS lets her down though without HP boost, rendering her BC on Spark useless outside of Arena. Inflicts Curse and Injury, valuable status ailments in Raids to lock Raid parts down. Good Spark Blanket which may use on FH squads; capable Arena lead
 * Avani - quaity Arena and CA leader, also a fantastic Spark buffer and Hit Count buffer. Has a higher Spark buff than Elza, but doesn't give team the ailment buff; BC on Spark on BB, and hence helps to fill gauges
 * Sodis - Spark-buffing mitigator, a unique combination that could warrant use in some squads
 * Will - BB mod buffer with HoT, but his BB mod is quite weak compared to Sirius (250%) and in future Cyrus (300%)
 * Carrol - strong tribuffer with 3 elements buff, also provides BC on attacked, directly outclasses Nadore; OD fill valuable in some content
 * Estelle - strong OD fill niche, provides BC/turn and also has HoT, useful in UBB spam strategies
 * Ciara - 4 Elements buffer, purely offensive unit outclassed by Rouche and Zeruiah and Allanon, but strong CA lead
 * Semira - premier status inflictor and cures ailments, missing Injury which could be useful but some Raid and Trial bosses are immune to it anyway. Might have a home in my top 20
 * Kira - niche unit for OTKing Medanche in Medal Rush due to his crit buff and Dark + Light Elemental damage buff; outclassed for FH/FG farming
 * Hadaron - CA lead who is good at focusing Raid parts. Doesn't carry much value outside of that as a sub
 * Dolk - strong defensive mitigator with negate elemental weakness on LS, also Def convert on SBB. Really deserved a spot above
 * Limera - Defensive leader for hard content as she gives Angel Idol on LS. Burst healer with elemental mitigation and can revive units on UBB. Almost a sidegrade to Phoenix
 * Farzen - Premier crit buffer who may see use on some Guard Frontier teams with Nyami, as such teams are pretty freestyle and composed of different types of buffers and Rize. UBB grants Crit, Spark vulnerability and BB mod buff, deserved a spot in my top 20
 * Drevas - elemental mitigator which can handle 4 of the 6 elements comfortably, is basically RC6's defensive king as he can also lock Raid parts down with status ailments reflect
 * Malbelle - infinite SBB, pioneer of the Critical Spark and the BB mod boost on SBB, also adds one-turn DoT, good for imp farming
 * Zelnite - sidegrade to Zeruiah if you ignore the Elemental buffs, due to EXP boost on LS; BC management buffs outclassed my Lafiel as BC instafill is not as good as BC on spark
 * Mikael - ST mitigator who excels in targeting parts in Raids; generally seen as a downgrade to Gazia in all other content due to sharing almost all the buffs, but is better than him defensively
 * Deimos and Ultor - both are Taunt units, with Deimos being more defensive and Ultor being more offensive. Ultor carries good value in CA, but both don't see much use anywhere, especially Deimos, except for cheesing Lem EX Dungeon (when Mora targets all rows except the middle; place the Taunter in the middle row)
 * Zenia - nukes virtually every piece of content in the game, has a niche in Elgif dungeon for her Hit Count buff and also in regular Arena. Good sub for Medal Rush with Kira leads
 * Rize - niche in SBB nuking FH/FG, with 2 Avant leads, Allanon/Zeruiah/Shida and Charla. Little use beyond this
 * Reud - All parameters LS with BC fill on attacked, specializes in filling gauges and comes with a weak Atk convert; HoT on BB may be useful in Trials and Raids

Trials:
Special Mention: Isterio, Krantz, Allanon, Chrome, Darvanshel, Reud
 * 1) Lafiel
 * 2) Laberd
 * 3) Haile
 * 4) Piany
 * 5) Phoenix

Raids: Special Mention: Nyami, Mikael, Hadaron, Charla, Gildorf
 * 1) Tridon
 * 2) Haile
 * 3) Korzan
 * 4) Allanon
 * 5) Drevas

Medal Rush: Special Mention: Reis, Farzen, Hadaron, Gildorf
 * 1) Kira
 * 2) Avant
 * 3) Nyami
 * 4) Zenia
 * 5) Charla

FH/FG Farming: Special Mention: Griff, Elza, Kira, Zenia, Shera
 * 1) Avant
 * 2) Nyami
 * 3) Charla
 * 4) Rize
 * 5) Farzen

Arena: Special Mention: Raaga, Lucina, Haile, Limera, Bestie, Zephyr (mainly Hit Count buff ES or LS units)
 * 1) Rahgan
 * 2) Avani
 * 3) Iris
 * 4) Hadaron
 * 5) Zenia

Challenge Arena: Special Mention: Ciara, Krantz, Hit Count buff ES units
 * 1) Hadaron
 * 2) Charla
 * 3) Avani
 * 4) Rahgan
 * 5) Haile

There are a lot of other uses for different units I may not have covered. Or perhaps you have a unit you really love. By all means, since this is a UoC event, pick the unit you really want! This is not a definitive guide after all.