And The Lowest Shall Rise…
In this guide we discuss some of the best low-rarity Operators (4★ and below). Low-rarity Operators have the advantage of lower DP and development costs than their 5★ and 6★ counterparts. However, in most cases, they should not be considered replacements for higher-rarity Operators, but rather gap-fillers until higher-rarity Operators can be obtained and resources gathered to develop them.
This guide is NOT an endorsement to max out these Operators. In fact, 2★ and 3★ Operators will not be viable for the average player in late to end game. There is no hard-and-set rule as far as how high to level low-rarity Operators, and each player should use their own judgment. However, if you are looking for some kind of guidance, it’s probably safe to say that most 3★s should not be leveled past E1 Lvl 30 and most 4★s should not be promoted to E2 (although there are exceptions). Just be sure you know what you are doing before you commit those kinds of resources.
Now, on to discussing the uncommon things about our commons!
Lancet-2 and Castle-3 are 1★ Robot units with several special properties. At full Potential, Lancet-2 restores 500 HP to all units on deployment at a very low 3 DP cost, making her excellent for use as an emergency heal. Castle-3, at full Potential and for the same low 3 DP cost, buffs the ATK and DEF of all melee Operators by 20% for 20 seconds, helping allies to survive a difficult wave. Because they ignore the Unit Limit, the Robots are also perfect for baiting a high-damage attack or an enemy's nasty special ability, even into the lategame.
Lancet-2 and Castle-3 can be very useful and should not be ignored. Their poor stats, however, make them fairly useless outside of the utility mentioned above.
12F is valuable because he is a cheap source of AoE Arts damage. AoE damage is very important on stages where you are swarmed by hordes of enemies, and sometimes you will need multiple AoE Operators to handle the flood. He also has high Physical Dodge from his Talent, which can occasionally come in useful for tanking ranged bosses (i.e., Faust).
Rangers’ strength is his Talent, which increases his ATK against flying targets by 50%, making him stronger against airborne units than some higher-rarity Snipers. He will be weaker against anything else, though.
Melantha is the poster child for “Don’t Ignore Your 3★s.” Her role is that of an assassin: she is dropped into battle to take out specific threats, especially solo enemy units in map corners, and then retreated. She has a low DP cost, is cheap to upgrade, and has surprisingly high stats for her rarity. She is a strong Guard in early game and has uses well into the late game.
When it comes to single-target DPS, Kroos has some of the highest damage of any Sniper below E2. Since her Skill is automatic and on-attack, she doesn’t need to be actively managed, making her very beginner-friendly.
Midnight is a 3★ Ranged Guard who can change his attacks into Arts damage with his Skill. He is outclassed by higher-rarity Ranged Guard Lappland, but having both can be useful, especially since Midnight can choose when to activate his Arts damage, while Lappland's Skill triggers automatically.
Beagle is a Normal Defender who is given to all players for free, and she's an outstanding earlygame Defender. She is outshone by higher-rarity Defenders like Cuora, but players often need two or three Defenders to block all enemy routes on a map, so Beagle can see use for a long while.
Lava is an AoE Caster with decent stats who can take care of those pesky enemy swarms until you get 4★ Gitano or 5★ Skyfire, who are overall upgrades. The player can choose between raising her, raising 12F, or raising both, since the two work surprisingly well together if other AoE options are lacking.
Ansel is a Medic whose unique Skill extends his range beyond that of most Medics, making him very useful for maps with certain placement options. He is a good starting healer until higher-rarity Medics are obtained for general use.
Fang and Plume are useful earlygame Vanguards with cheap DP costs. Fang generates more DP than Plume, but Plume is better at killing enemies than Fang. Both are outclassed by their direct 4★ upgrades (Fang to Courier, Plume to Vigna), but they are still good secondary Vanguards through the early- and mid-game. Even in the lategame, they can be helpful for maps with fast starts or where a few extra DP at the beginning will make a big difference, such as some of the highest-level DP-generation-down Contingency Contracts.
As a Utility Vanguard, Myrtle is one of the best DP-generating Vanguards in the game. She blows every other Vanguard archetype out of the water with her DP-generating Skills and she can heal allies to boot, making her one of the best Vanguards in Arknights. (If you don't pull Myrtle early on, Credit Store Operator Courier is probably the best substitute, being an easily accessible Skill-DP-Recovery Vanguard.)
Cuora is a Defender with one of the highest DEF stats in the game. She is also one of the few Operators who can Block 4 enemies (with the use of her S2). She is excellent against high-ATK bosses and elite units that deal physical damage--in fact, Cuora is one of the few 4★ units to see use in high-end content. The downside is that she is very weak to enemy Casters.
Perfumer is an accessible AoE Medic whose Talent passively heals all Operators on the field for a percentage of Perfumer's ATK. This allows her to heal allies outside of her range, and it even bypasses the "Cannot be healed by allies" Trait that some Operators possess. The power and versatility of Perfumer's global healing makes her a viable healer in just about any content.
If you're in need of a strong ST Medic, Sussurro is the perfect doctor for the job. Her S2 packs some of the most concentrated healing power in Arknights, with the disadvantage that it can only be used twice per map. However, twice is more than enough to get through most maps (except the really long ones, like Annihilation runs).
Gummy is a Healing Defender, which means she combines aspects of a Defender and a Medic in a single unit slot. She can Block-3 after being promoted to E1 or higher, and her Skills heal adjacent allies. Healing Defenders are prized for their versatility, and Gummy is also very accessible, as she can be purchased with the $0.99 Starter Pack in the Store.
Vigna is a DP-On-Kill Vanguard with incredible offensive presence for her rarity. She won't typically generate as much DP for the team as a Skill-DP Vanguard, but she makes up for it by being able to bring heavy DPS throughout a map, long after your DP needs have been met. She's also an excellent assassin, since being a DP-On-Kill Vanguard means she refunds her DP cost every time she is retreated.
Gravel is a defensive Fast-Redeploy Specialist. She is great for baiting strong enemy abilities, delaying enemy flow, or "catching" solo enemies that get through the frontline. Although she can tank a few hits from stronger enemies with her defensive Skills, her low ATK makes it difficult for her to kill things. She requires a bit of practice to use properly but can be a very useful utility Operator.
Shaw and Rope are 4★ Shift Specialists whose Skills allow them to push (Shaw) or pull (Rope) enemies. This can be used to move enemies into lethal terrain like pits, to force enemies away from your frontliners, or even to pull off advanced tricks like changing enemy movement patterns. Shift Operators need high Skill Levels to move heavier enemies, and Shaw and Rope are the lowest-rarity Shift Operators, making their Skill Levels the cheapest to increase.
4★ Gitano is arguably one of the better AoE Casters in the game due to the utility of her S2, which increases her attack range and allows her to hit all enemies in the area at once. This is something even higher-rarity Casters can't duplicate, giving her a unique niche when you need AoE Arts damage across a particularly wide radius.
ShiraYuki is an AoE Sniper with two interesting Skills. S1 increases her attack range by 2, giving her a crazy long reach. S2 changes her attacks to Arts damage and adds a Slow effect, giving her extra utility and tank-killing potential. She's a massive improvement from 3★ Catapult, and her utility gives her a niche even when compared to higher-rarity AoE Snipers.
The following Operators have very niche uses and are only mentioned to inform the reader about their unique abilities.
Durin's Talent gives her an enormous amount of Arts Dodge. Similar to 12F and his Physical Dodge, this occasionally makes her a great low-investment "tank" against bosses with Arts attacks, such as the Rat King.
3★ Caster Steward is overshadowed in most cases by 5★ Caster Amiya, who is given to all players for free when they start Arknights. However, Steward's Talent causes him to prioritize attacking the target with the greatest DEF. If a player ever finds themselves in a situation where their Casters are being distracted by lower-DEF targets and it is causing problems (i.e., when armored drones start hitting the field), then Steward might be worth considering.
Mousse is a 4★ Arts Guard, making her one of the few melee Operators in the game who deals Arts damage, and she's also one of the few Operators who can debuff enemy ATK (S1). Her niche is not necessary in the earlygame, and she can be hard to use well due to having a high DP cost and only Block-1, but she shines in challenge content where Arts damage is required but Casters are limited or outright unable to be deployed.
4★ Utage is an Enmity Guard with some of the highest on-deployment DPS currently in Arknights. Her Descending Strike - Earth Splitter Skill gives her a huge ATK boost, turns her attacks into Arts damage, and starts her at half HP in order to trigger an attack speed boost from her Talent. She is incredibly powerful, but Doctors should be aware that she is NOT beginner-friendly to use. She can't be directly healed by other Operators (so the HP loss from Descending Strike can screw you up) and Descending Strike is an on-deployment Skill, making it difficult to use multiple times in a fight.
Matterhorn is often outclassed by other Defenders, but one area he excels in is tanking Arts damage. At E2-promotion with a maxed-out S2 active, he has a whopping 40 RES, allowing him to shrug off Arts damage like a light summer rain. It's a lot of investment, but if you're really struggling with enemy Casters, Matterhorn might be a good addition to your team.
May is a 4★ Sniper who can Slow and Stun enemies using her super-special Secret Detective bullets (disclaimer: may not be super-special or Secret Detective). She doesn't have the highest DPS of the 4★ Snipers, but her crowd control capabilities make her an excellent utility unit and possibly one of the better 4★ Snipers to consider raising long-term.
Frostleaf is a 4★ Ranged Guard and Ethan is a 4★ Controller Specialist, but despite their different classes, they have something in common: they're both ground-deployed Operators with useful crowd-control Skills. Frostleaf can Slow or Freeze enemies with her Skills, and Ethan can Bind enemies with his Talent. Both are very niche, but they can be extremely valuable for stalling strategies.
Deepcolor is a 4★ Summoner Supporter who specializes in stalling strategies. Her tentacle minions can be useful for baiting strong enemy abilities, delaying enemy flow, and "catching" solo enemies that get through the frontline, and the AoE Physical Dodge buff on her S2 is extremely potent. It takes a bit of practice to use her properly, but once you get the hang of it, she can be a useful utility Operator.