Always go Ignite. Rakan is an all in champ and you want all the all in power you can get. DON'T TAKE EXHAUST!
Q max is essential for the lane poke, since that is pretty much everything you will be doing before level 6. E max second for the lowered cooldown and shield strengh.
IF you are playing with Xayah, skill level 1 ONLY IF SHE ALST STARTS W!! That way you can level 1 all in for first blood.
Most enchanter supports are fairly easy for Rakan.
Some think Tahm is tanky but he can't use his 10K health shield while charmed which makes it fairly useless.
Light/medium poke supports are fine for Rakan as long as you can land some Q's to heal you and your AD back up.
Hookers are a hit or miss (no pun intended) as they can all in before level 6 (you can't).
Fiddle is sometimes awful due to his ability to fear you in your ult. Bait the terrify and you should be fine.
Rakan's worst matchup by far.
Hard poke supports like Zyra/Brand can easily kill you level 3/4-ish. Fairly hard to counter heal them too.
The worst hooker matchup. Pyke is so dominant in lane that he can dominate Rakan fairly esaily.
Rakan - The Charmer
Rakan is a high mobility, all in engage support who finds most success by hard engaging in late game teamfights, making it easy for your team to score the ace. On the contrary, Rakan struggles in lane. He has a very, very weak lane before reaching level 6 (although he does have one of the best level 6 powerspikes), which makes him fairly vulnerable to snowball champs and early game supports / AD's.
Once mastered, Rakan can be played in a lot of different matchups (even the tough one's exept Morgana) and can be paired with almost any ADC, late game hypercarries like Twitch or early game dominators like Draven or Lucian.
The Laning Phase and Rakan's main combo
Once you reach level 6 and learn
The full Rakan combo now goes
Late game as Rakan
Rakan is probably one of the best late game engagers you can have on your team if played right. Going back to the full combo above, instead of immediately dashing after ulting, you now want to wait with the dash until you have charmed multiple enemies. The rank 3
Some people like the