Alhaitham (艾尔海森) is the first dendro dps introduced in the game and is an upgrade from keqing.
His kit looks like a carbon copy of Keqing's, perhaps to symbolize the connection between Aisin Gioro and the Qing dynasty (Aisin-Gioro founded the Qing and were the Qing emperors).
His E can teleport him to places and give him dendro infusion. His Q is multi-hit.
However, there are important differences. Whenever he has chisel mirrors, he will have dendro infusion. Moreover, attacking while he has mirrors will do an extra projection attack. He can have up to 3 mirrors. The more mirrors he has, the more damage his projection attack does.
His projection attacks have very good aoe and high scalings, and this is one of the upgrades from Keqing. Each mirror will make the projection attack do an extra instance of aoe dendro damage. So 3 mirrors will do 3 instances, 2 mirrors will do 2, and 1 mirror will do 1. The projection attack can proc every 1.6s. They have a unique ICD, following a 2-hit rule. That is they can apply dendro / proc dendro reactions once every 2 hits.
Every 4s, Alhaitham will lose one mirror. His E can give him 1-2 mirrors (2 if he has none before casting his E). He can also gain 1 mirror by doing a charged/plunging attack (once every 12s). His Q can also give him mirrors. It will give 3 minus current number of mirrors. So if he has 3/2/1/0 mirrors, his Q will give 0/1/2/3 mirrors respectively. (At C6 this changes as his Q will give 3 mirrors no matter what.)
One of his passives converts EM to dmg bonus on E projection atk and Q. 1000 em will give a max of 100% dmg bonus. His E projection attacks and Q have dual scaling (scale with both atk and em). Thus, Alhaitham has quadratic EM scaling.
His NA sequence involves him kicking his sword and using dual blades. His signature weapon also has 88% crit dmg. So he has joined the weapon kicking, 70 energy cost, 88% cd gang along with Itto and Yelan.
On his dual atk-em scaling: the atk scaling is like the base salary, while the em scaling is like the bonus. Together they form the total compensation. When the market is good, the bonus can be twice the base salary, as is the case for Alhaitham's E projection attacks.
Alhaitham is a very flexible character. In overworld if needed for quick dendro application, one can just use a CA to gain one crystal (with a 12s cd). If one faces a bit more serious enemy, one can use E to gain two crystals and more damage (with a 18s cd). If facing tougher mobs and bosses, one can use E midair + plunge or his burst to gain more crystals.
C1 decreases E cd. C2 gives up to 200 em (50 per mirror). C4 gives EM to rest of party and dmg bonus to Alhaitham depending on number of mirrors consumed/generated by Q. C6 gives bonus cr and cd and allows his Q to generate 3 mirrors each time.
Specifically, C4 gives 30 EM to rest of party for each mirror consumed by Q for 15s. So it gives up to 90 EM to rest of party for 15s, which is more than baizhu's C4. In other words, baizhu is a basket case, especially when Alhaitham, a dps unit, provides more support than a supposed support unit.
Gilded is bis for damage. Do EM/ATK sands, dendro goblet, crit circlet.
Best 5 star weapons include foliar, jade cutter, mist, etc. Best 4 star weapons include the Dongfang Inazuma umbrella weapon, iron sting, blackcliff, harbinger, festering.
He synergizes well with Nahida, Yaoyao, Raiden, Yae, Kuki, Kirara, Furina, Yelan/XQ, Kujou, Nilou, Fischl, Barbara, Beidou, etc. He can be played in spread and quickbloom teams. The following gives some example archetypes.
Quickbloom / Hyperbloom:
Spread:
Bloom / Burgeon / Rainbow:
Miscellaneous:
Assume 4p gilded with 46.6% dendro dmg bonus. At lv90, Alhaitham gets 28.8% more dendro dmg bonus. Suppose he gets 180em from gilded, 100em from dendro resonance, and 120em from other sources (weapon, artifacts, Nahida Q, etc.). So suppose he can reach a total of 400em for a typical build. This will give 40% dmg bonus on his E projection and Q. So in total he can reach 115.4% dendro dmg bonus.
Suppose he is run with Bennett and can reach 3k atk. His E projection has 120.96% ATK + 241.92% EM scaling per mirror, and the rush attack has 348.48% ATK + 278.78% EM scaling at lv10. The E cd is 18s. For 3k atk and 400 em, the 100% EM scaling is equivalent to 13.3% ATK scaling (divide by 7.5). So the E projection is equivalent to $$120.96+32.256=153.216$$ ATK scaling per mirror (the EM scaling gives around 27% more damage). For different atk and em stats, this will differ, but we use this for this calculation.
Alhaitham is a very flexible character given that he can gain mirrors via different ways and can have different kinds of rotations. He can be played as an on-field carry and as a quickswap unit.
As an on-field carry, his rotation may look like: start with 0 mirrors, use Q to get 3 mirrors, use E after 4s to refresh, use CA/PA after 4s to refresh. This will give him 12s of dps with 3 mirrors. After that he can swap out or continue to dps with 1-2 mirrors.
For now we will ignore his NA, CA, rush damage, and Q damage. During those 12s, he can do 6 projection attacks with 3 mirrors or 18 hits. This gives a dps of $$18*153.216*2.154/18 = 330$$ without reactions.
Given his unique ICD, he can spread half of those (or 9 hits). At lv90 and 400em, the flat dmg bonus from spread is about $$1446.85*1.25*(1+(5*400)/1600) = 4069$$ This is equivalent to 136% extra scaling per spread (normalizing to 3k atk). So the projection dps with spread is $$x_p = (18*153.216 + 9*136)*2.154/18 = 476.5$$
Above we considered as 12s rotation with 3 mirrors and 6s off-field (for supports). But technically his dendro infusion will still last after 12s. It will be 2 mirrors for 4s and then 1 mirror for 4s, giving him 20s of dendro infusion (100% uptime if he has Q up all the time or since his CA/PA infusion passive has 12s cd). All this shows is that the cd reduction from his C1 is somewhat superfluous since he can already achieve 100% uptime on dendro infusion. Something like more scaling on E or shredding def against quicken enemies (or making bloom/hyperbloom/burgeon crit) would have been better.
The 100% uptime on dendro infusion plus his frontloading ability not only gives him high personal damage but makes him very effective as a dendro reaction enabler (for say hyperbloom) as he can create many bloom seeds.
At lv10, each Q hit has 218.88% ATK + 175.1% EM scaling. Assuming 3k atk and 400 em, this is equivalent to about 242.23% atk scaling per hit. Suppose Alhaitham uses his Q on cd and each time starting with 0 mirrors. His Q will hit 4 times. It has a cd of 18s. The dps is $$4*242.23*2.154/18 = 115.9$$ without reactions. He can spread two of those hits, making the dps $$x_q = (4*242.23 + 2*136)*2.154/18 = 148.5$$
Adding his E projection with Q damage gives a dps of $$x_p + x_q = 625,$$ which is very high (top tier). And this is not even considering his NA or rush damage.
There is another playstyle, using Alhaitham as a burst nuker quickswap. It involves using his Q each time with 3 mirrors (e.g. hold E + plunge). The Q will then hit 10 times. The dps is $$10*242.23*2.154/18 = 289.9$$ without reactions. He can spread 4 of those hits, making the dps $$q_{10} = (10*242.23 + 4*136)*2.154/18 = 354.9672333333$$ This is quite high among nukes, but as shown above his 0 mirror Q dps (on-field 12s rotation) has greater dps than just using him as a quickswap nuker (like Ayaka or Xiaogan). But Alhaitham does have the ability to frontload his damage with hold E + plunge (for immediate 3 mirrors) and then either burst nuking or sustaining on-field dps for 12s.
There are perhaps calculations for intermediate playstyles such as 1 mirror Q and 2 mirror Q, all adding to his flexibility as a dps. These calculations have focused on the two extremes 0 mirror Q and 3 mirror Q for now.
But at C6 you can have both playstyles (0 mirror Q and 3 mirror Q). You can consume 3 mirrors for the max burst and get 3 mirrors back for sustained dps.
Suppose in the 12s where he has 3 mirrors, he can do his full 5-hit NA combo 4 times. At lv10 his NA combo has 631.07% total scaling. With 4p Gilded and his ascension it will have 46.6+28.8=75.4% dendro dmg bonus (his passive buffs his E and Q dmg, it could have given straight up dendro dmg bonus for everything like Raiden's energy to electro dmg bonus conversion passive). In an 18s rotation, the dps is $$x_n = 4*631.07*1.754/18 = 245.9770622222$$ without reactions. But even then one can see by adding this mv to the above E+Q dps, Alhaitham's personal damage gets very high.
Suppose his NA has standard icd with 3-hit rule (here we ignore the 2.5s reset for simplicity). Then in 20 hits of his NA, he can spread say 7 of those. The dps is then $$x_n = (4*631.07 + 7*136)*1.754/18 = 338.7441733333$$ So spread can buff his overall NA dps by nearly 1.5 times.
Adding his NA + mirror + Q damage, his spread dps becomes $$x = x_n + x_p + x_q = 963.7441733333$$ And this is ignoring his E rush damage (and possible CA/PA). Moreover it ignores other reactions like hyperbloom that can increase his (team) dps further.
Needless to say this dps is top among C0 carries (and already around the level of C6 dps). The hero is overpowered.
In Chinese, Islam is also called 清真 or Qingzhen, perhaps befitting of one of the greatest Islamic scholars of all time Al-haitham. The scientist Alhaitham specialized in physics and optics, which fits how his kit centers on mirrors and light. He lived during the Islamic golden age, before the Mongol empire and the European Renaissance. Long ago, when Europe was backwards and dealing with the plague and nomadic invaders, the Middle East was actually the center of western civilization. The contributions of Islamic scholars actually laid the foundation for later European breakthroughs in science and technology. Europeans borrowed many loanwords from Arabic, including algebra, the branch of mathematics. And for thousands of years, parts of Europe including Spain were ruled by the Muslims.
Some Eurocentrists then like to point out that the Muslims borrowed a lot of their culture from Greece and Rome (Alexander's empire and the Roman empire). The genius Islamic scientists based their works on even older Greek scientists such as Euclid and Ptolemy, while the Islamic religion is Abrahamic like Christianity from the Roman empire and Judaism.
While it's true that the Middle East borrowed some stuff from the Greeks and Romans, if you go further back in history, where did the Greeks and Romans borrow their culture from? The Greek and Roman alphabets are based on Middle Eastern scripts such as Phoenician and some Egyptian scripts. Many Greek gods were borrowed from Sumer based in modern Iraq. It is not a stretch to say that the Greek and Roman empires were Middle Eastern empires as well given their geographic stretch, with Alexander's empire covering much of Egypt and Persia and the Romans reaching Syria and the borders of Iraq. The Middle Eastern cultures of Egypt and Sumer predate even the Roman and Greek civilizations. Throughout the history of these regions, there has always been an exchange of culture and ideas between Europe and the Middle East, oftentimes in the form of war and conquest.
The Ai 艾 in Alhaitham is different from the 埃 in Egypt (埃及). It is also different from the 爱 in Aisin-Gioro (爱新觉罗). By contrast, Klee's mother Alice actually uses the imperial character 爱 (in 爱丽丝).
Also, the Al in Alhaitham is a bit different from the Al in Alexander. In Arabic, Al (ال) means 'the', whereas Alex is based on a Greek word meaning 'defend'. The fact both begin with Al could be a coincidence. Al is just a really common sound in the European and Mideast languages, appearing in words like algorithm, algebra, etc. It is also funny that the game compares the strength of Cyno and Alhaitham.
The Ai in Alhaitham's name also connects to numerous other genius scientists and inventors in history, including Edison, Einstein, Isaac Newton who share that same sound in their name. During the Sumeru quest story, Alhaitham also discusses some machine learning and AI algorithms. And coincidentally, Alhaitham shares the same birthday with Thomas Edison, inventor of the lightbulb.
The name of Alhaitham's Q contains another allusion to the name of a Chinese person (and his wife) who helped set up a certain science foundation at a certain elite university in the USA.
Alhaitham's roommate Kaveh got in trouble for smearing Alhaitham too much for no good reason.
Alhaitham's C4 could be a reference to the crimes of Li Yijiang, a serial killer.
On Alhaitham's connection with Chinese culture: it is somewhat significant that Alhaitham released in 3.4 during Lantern Rite, which corresponds to a Chinese holiday. In the past, Lantern Rite has only ran with Liyue characters only, so Alhaitham is almost like a guest of honor.
But as mentioned earlier, Alhaitham's design itself is an allusion to the Aisin-Gioro clan who founded China's Qing dynasty. And some of his voice actors and other parts of his name allude to different people that were oppressed by the Ming dynasty, the predecessor of the Qing. The names of several of Alhaitham's talents and constellations allude to different kingdoms/people that the Qing dynasty defeated in its quest to unify China: including conquering Taiwan, a kingdom in Sichuan, a dynasty in Beijing, the Southern Ming, suppressing a rebellion in Taiwan (during the Qianlong era). The name of Alhaitham's signature weapon also alludes to 1) the clan of the empresses married to various Aisin-Gioro emperors (perhaps related to how Yelan reran in 3.4 after Alhaitham) and 2) another clan that was oppressed by the Ming elites.
And the Lantern Rite in Chinese is also called Haidengjie (海灯节) or Festival of Sea of Lights. At the end of the Qing dynasty, many of the Man people and Aisin-Gioro clan adopted Han Chinese surnames. Aisin-Gioro means 'gold' in the Man language, so many adopted the surname Jin (金), meaning gold in Han Chinese. Incidentally, Jin is related to Xiao, who reran alongside Alhaitham. Other Aisin clan people changed their surname to 'Hai' (海), related to the Haidengjie, as well as the name of a person oppressed during the Ming dynasty. Even a play was written about this person and presented to Mao Zedong.
Lastly, the Dongfang EM umbrella sword from the 3.3 Inazuma event alludes to another person that was executed during the Ming. This sword happens to be one of Alhaitham's best 4 star options.
The Ming dynasty executed and oppressed too many people.