Focus

Overview

 * The Focus is a powerful tower, sometimes compared to the Lightning for its properties, particularly for their anti-heavy capabilities.
 * It's also an anti-heavy-one tower that keeps the high fire rate at the same time, in the opposite of most other such ones.
 * It has a railgun-like outlook and fires a constant beam at an enemy. The beam gets bolder and the damage increases as it focuses on the same target, up to 5x the starting damage.
 * One should be wary that the bonus is amplifying only the damage, reached by upgrading and overcharging. This means that an Amp spire& additive types of tower-perks would not result in a multiplied amount of overall damage, but the damage buffs would only add-up instead, thus making the warming-up effect technically an up-to 400% separate 'Amp' by itself.

Trivia

 * Previously in Sanctum 1 the Focus ' tower design was used in the Penetrator tower there, which there is able to penetrate and hit secondary enemies, instead of multiplying the damage. (link to the Penetrator's info page: [1 ])

Notes & tactics

 * Because of the focus property, the Focus has one of the highest single-targeted DPSes and DPS per resource vs ground enemies once it has warmed up.
 * Of course, the Anti-air beats it vs flying lumes at level 2 & 3, regardless of whether the Focus is warmed-up, while also having area-of-effect and bigger range, but is limited only vs air lumes.
 * The Orbital strike relays can potentially deal more damage vs single lumes during the strikes, especially if they are slowed, stunned or kited properly; can damage multiple enemies and the tower range is higher. However, they have their own issues - strikes occur with a low rate, cannot hit flying lumes, depend on the lumes' speed more sharply and on how many lumes will be hit during the beam and therefore find less application than the Focus. Additionally, the area-of-effect is very small and hardly can compare with the ACP's potential vs multiple lumes.
 * The Drone's capabilities randomly can find better use than the Focus'. Since a Hoverer/Hoverer queen has an invulnerable front, this technically means 50% of the time it wouldn't take damage from the Focus and a Drone can hit up to 3 Hoverer-things at once. While the damage can be improved a bit via kiting the lume, the Queen usually should not be approached when there are towers nearby, thus making the kiting problematic, and if a semi-invulnerable lume is showing only her front to the Focus, this might produce a lot of trouble in some maps, particularly in scenarios when the Hoverer stretches her body in a certain angle, like how it can in 3-2: Train Station and 6-1: Shortrcut. Clearly, the Focus cannot damage Bobble Heads and Fiskeplaske, thus opening a good utility spot for the Drone if tower damage vs these lumes is needed. Using a Drone often can find better use than the Focus in Survival mode, depending on the map, especially since it is much less dependent on tower sight.
 * Enemies and Focus
 * This tower shines mainly vs the heaviest enemies, with a specific accent on the three ground bosses. The Soakers, Armoured heavy & the Spore keepers are also pretty susceptible.
 * The Walker warriors and Screamer matriarchs are other somewhat-heavy lumes, that the Focus can shine against.
 * Average lumes like Walkers, Mutators & Heavy pups are mostly neutral to whether thay are hit by Focus, Friendship lasers, Cannons or almost any alternative since results appear similar.
 * The enemies that the Focus struggles against are the smaller and the faster ones
 * Runners, Brood mothers, Walker pups, Snorkers, Screamers, Rhinos, Jumpers and crawling Infected explorers all are low on height and can easily "hide" even behind tower bases and then the Focus might sometimes visually 'fire' at them, but dealing no damage. Of course, if these are close enough and the obstruction is away, the Focus would finally do its job. On the other side, all of these are mostly easy to kill or to wound heavily with ACP with or without a Range spire after a certain moment.
 * Fast enemies would often escape the Focus at eaze. While Rhinos usually can be held long enough by creating some maze twists close to the Focus, the Runners & Brood mothers would often run away with their lives. All fast enemies are more susceptible to the ACP and bursty towers like Lightnings & Violators (if the burst-towers are enough in numbers).
 * The Focus easily falls behind many other towers when it comes to crowds. Would it be average or smaller lumes, it hardly can compare with anti-crowd towers such as the ACP, so the Focus tower often might not be the best choice to rely on vs the multiple lumes, depending also on the map and wave. The reason lies mainly in the constant loss of the warming-up effect between the killed lumes and this hardly can be overcome by using multiple Focuses, neither would they have the same overall damage efficiency with the lowere sight and therefore less range utility. There are scenarios when even the high fire rate of the Gatling can become unable to deal with heavy counts of usual enemies, regardless of the overcharge, and the Focus has less than half of its attack speed.
 * Clearly, the Focus cannot do damage vs Bobble Heads & Fiskeplaske, that are vulnerable to Drone on their own, while also bobbles suffer high damage from Rupture mines.
 * Hoverers are vulnerable on their backs and so do Hoverers queens and this tower is still among the better options vs them, although it easily falls behind if Drone(s) are/is used vs the usual Hoverers with or without slows & stuns, and/or if there is a high usage of mines, would it be AR or Rupture-ones, that are highly capable vs both the boss lume and the Hoverers.
 * Targeting system of the Focus
 * To ensure that it stays focused on the strongest enemies and deals the most damage possible, it is recommended to set its targeting priority to "Most Health" in most scenarios;
 * If there are lumes with partial immunities (infinite armor) like Bobble heads & Hoverers, the targeting should be adjusted to evade targeting them whenever possible. This might sometimes lead to the 'Least health' option being a lot better choice in the certain scenario. The 'Closest' or 'Default' targets are also options, particularly if the players can deal with the unwanted lumes before they reach the range of the Focus.
 * In the last wave of Laser bridge the boss Fiskeplaske is invulnerable to the Focus, so setting it to "Least health" then is a generally better option than leaving it to the opposite, although in this scenario this 'd produce good effect mainly if the Focus is not too close to the spawn points, since then it still might keep wasting its power into the boss for very long, instead of dealing with the ground lumes that can arrive faster at the core. The Focus would not stop firing at its target until it dies or goes out of the tower's range, like all towers with targeting system.
 * If there are Mutators, it is sometimes better to leave it to "Least health", since then the Focus is more likely to kill them first and reduce the further mutations.
 * The damage bonus from warming up vanishes immediately when the tower switches its target. Thus, it is beneficial to construct a maze around it that leads a long track through its range without interruptions. If the focused enemy just shortly leaves and re-enters its range, the bonus is lost and it has to warm up again.
 * Around a Focus, the players should usually attack the focused enemy last to make sure the Focus spends more time firing further warmed up on average. If they kill the focused target quickly, the Focus will reset more often than if they skip the focused enemy to instead attack the next in line (or any other).
 * Similarly, the Focus is more effective if it is the only tower assigned to attack the strongest enemies within its range. If other towers prioritize them as well, they die more quickly, forcing the Focus to switch its target and lose its bonus more often. This includes having multiple Focus towers in the same area.
 * The Focus can be assisted relatively well with controlling the lumes (slowing, stunning & holding/kiting measures) to prolong the time enemies spend within its range, e.g.:
 * Slows from Kairos, Slow Fields, Slowing Rounds or Slowing Presence
 * Tanking behavior from players, G-2 companions, Simo units (from Roboticist & map-specific ones from the Arc islands) and Explorer conscripts (from Reinforcements, Best friends forever & map-specific fighting ones).
 * Concussion rounds with proper weapons, with/without other perks like Marksman.
 * Mind Control Spire(s), although they are secondary after the other support towers and the Focus has high fire rate, so is not too dependent.
 * Makeshift cannons can also give their help by stunning an enemy from time to time, holding him for more DPS from the Focus. These usually need to be more for a bigger stun rate, but also shouldn't be too many, in order to not block the sight of the Focus.
 * Exploding explosive barrels in the Focus ' range when lumes are nearby, if the map has such.
 * Exploding the purple plant in Jellyfish cove if a Focus has range to the stun zone.
 * The best support tower for the Focus is the Range spire, since it allows the tower to concentrate onto a target for longer and therefore to get warmed up faster and from a bigger distance than it otherwise would.
 * The Amp doesn't quite meet the helpfulness of the other support towers. It does improve the damage, but the warm-up effect of the towers just stacks additively to the Amp's bonus, like if it is just an another specific adding-up amp itself.
 * The Focus might lock on targets within its range it cannot hurt, either because there is an obstacle blocking the line of fire (walls/rocks/etc, even the core itself), or the lume has infinite armor (Bobbleheads, Fiskeplaske and the fronts of Hoverers & Hoverer queens). A core ca n also block the Focus ' laser if close enough. If the Focus gets into a stalemate like this, where it is locked on a target it can't damage for some time, it becomes your first priority as a player to kill this target as quickly as possible, since the tower's effective DPS is 0 as long as it remains in that stalemate, wasting a lot of its damage potential.
 * Hoverers & Hoverer queens can be kited a bit in order to force them expose their backs to the Focus (= to make them put their fronts in the opposite direction). When it comes to the Queens, however, this has to be performed more carefully, since their attacks stun towers, caught in the attack range.
 * Overcharging the tower gives 40 damage per 100 resources, which is 73,85% of the damage, gained by building level 3 Focus towers.
 * Amp spire correlations are problematic and related only to the non-warmed (base) dmg of the Focus, since this tower's synergy with Amp spire, Tinkerer, Engineer & Core-tower synergy is the worst in the game. Anyway:
 * A level 1 Amp adds the same amount of base+overcharged dmg as overcharging a Focus to more than 370 damage and adding such Amp before further overcharging makes for a bigger damage gain.
 * A level 2 Amp adds the same amount of base+overcharged dmg as overcharging a Focus to more than 463 damage and adding such Amp before further overcharging makes for a bigger damage gain.
 * A lvl 3 Amp adds the same amount of base+overcharged dmg as overcharging a Focus to above 625 damage and adding such Amp before further overcharging makes for a bigger damage gain.
 * Overcharging the Amp adds the same amount of damage as overcharging a Focus to above 2000 dmg and from then on, max dmg gain can be reached by putting equal amounts of resources between them.
 * These correlations are in action for the damage, reached only via overcharging, without Tinkerer, Engineer, Core-tower synergy or already existing Amp spire. If any of these is in action, it is needed to calculate the damage, gained by pure overcharging (or to remove the buffs) to see the real efficiency stats. These 4 mentioned buffs stack additively with each other.
 * Like mentioned, the amp spire amplifies only the base+overcharged dmg of the Focus. The 4x bonus of the Focus does not multiplicate with other bonuses, just adding-up with them. At a certain long-game moment this might easily set the Focus behind the single-tower damage of some other towers, e.g. Gatling, since they would be buffed by the Amp for superior damage, regardless of the Focus' warm-up effect.
 * A sample moment when a Gatling would beat the Focus is like this: 2445 res. have been spent for the damage tower and the Gatling is overcharged for 1000 while the same for the Focus 'd be 1300 value (apart of any external buffs) and an Amp is overcharged for 300% bonus damage in both cases. The damage per second, dealt by the Gatling 'd be 26600, while the fully warmed-up Focus 'd deal 26000. This difference 'd come earlier and sharper with more overcharge of the Amp and with other active buffs like Tinkerer, Engineer, Limiter removal or Core-tower synergy. Despite of this, equations like this usually take impact in Survival mode, since overcharging the Amp to such values requires lots of resources.
 * The Focus tends to work better if it is a sole overcharge one or very few, instead of using multiple Focus towers, similarly to the ACP, Gatling, Anti-air & Drone.
 * The main reason is the problem with the sight obstructions. The Focus is a projectile-type of tower and as such would have issues if its damage is blocked by anything in its range, would it be a wall, rock or another tower, even another Focus, etc, which would easily result in lower overall DPS. Keeping towers less makes it overall easier to not crash the beam in obstroctions. If the Focus' sight is blocked, it would visually still fire, but dealing no damage. Technically the Focus is arguable the projectile-tower, that suffers the most from sight/space obstructions in the game, particularly since it also randomly appears to fire and target into the nothing, since its enemies cannot be damaged behind obstructions. Multiple Focus towers are more likely to lower the overall expected damage, regardless of the lower theoretical DPS when overcharging. There are some towers that would mostly not produce such issues, so could be rather safely put anywhere around - the Anti-air, Violators, Drone & the dispensers.
 * Projectile-using towers that suffer from random sight/space obstructions are the Scatter lasers & the ones with targeting system.
 * Another reason lies in the enemy armor. The level 2 & 3 Focus without overcharge is mostly capable of overcoming flat armour, but is not as quick in it as the overcharged one. The situtation with armour can become sharper if there are lots of armoured enemies, e.g. in the maps of Outskirts (from The pursuit DLC). Bearing in mind that the Focus is the tower that one would often rely the most vs armoured enemies, it is wise to take measures, would it be an Amp or overcharging a sole Focus/limited number of Focuses to bypass this natural defense of some lumes.
 * The fire rate of the tower in-game is converted into shots per second this way: One in-game speed unit is 1/60 shots per second and therefore come the calculations:
 * a level 1 Focus has 120/60 = 2 shots/sec ( = 120 shots per minute = 1 shot every half-second), which is the same as the fire rate of a level 1 Cannon;
 * a lvl 2 one has 133/60 ~ 2,217 shots/sec ( = 133 shots per minute ~ 1 shot per 0,45 seconds);
 * a lvl 3 Focus has 150/60 = 2,5 shots/sec. ( = 150 shots per minute = 1 shot per 0,4 seconds), which is the same as the fire rate of a level 1 Scatter laser.
 * This tower finds good use mostly in average/low-resource games or in specific gamestyle that would highly press on overcharging purely the Focus. Its lack of good scaling with additive %-bonuses such as that of the Amp could easily exclude the tower from high-resource games, since to reach maximum damage with very important towers such as the ACP, an Amp overcharge might be needed. The Gatling has better co-scaling, and while if overcharging only the Focus, it would technically always have higher single-target damage, if the player has to overcharge the Amp as well, the Gatling could prevail at a certain moment, regardless of the Focus' warm-up. Using Tinkerer, Engineer or Core-tower synergy might lead to an earlier or sharper reach of this tower state. Clearly, the Gatling has better burst damage as well, so it could offer good comparative capabilities in lower-resource games as well. The Focus would always be behind the Anti-air vs flying lumes and performs worse than the Drone and the Gatling at making Soakers more vulnerable. The ACP beats the Focus when it comes to crowds at ease, especially if there is a Range spire. While the Drone might be a must in some occasions, including in Survival mode, to deal with Bobble Heads, Fiskeplaske and Hoverer-type of lumes while also greatly helping vs Soakers, the Focus is generally a non-must tower in Survival mode, since it can be replenished with towers that have better potential and scaling.