Singed right now

Singed is just bad at the moment. He fills the role of a bruiser who relies heavily on staying alive as long as possible in fights to not be useless, but his lack of mobility and core items prevent him from surviving long enough to have an impact with his incredibly low range. He's honestly a worse Dr. Mundo at the moment, they aim for the same goals during teamfights but Dr. Mundo does the job better in every way. Singed arguably has a higher ceiling for effectiveness in any given fight but the requirements for it are impossible to fill at even platinum or higher, and he won't ever be worthwhile in high level 5v5 games. Singed just dies too fast, and he doesn't really function as a splitpusher even though he's a great duelist, because of his low range and mobility.

The Solution

Could this be an effect of people playing Singed incorrectly? No I'm not talking about his skillshots. My theory is that Rylai's Crystal Scepter is actually pretty bad at the moment, ESPECIALLY for singed. And the same goes for other items that used to be strong on him, but people heavily overrate them at the moment. Singed dies too fast WHEN you build Rylai's Crystal Scepter and 1-2 other offensive items, so why don't you just build him fulltank? With the flat AP gained from Insanity Potion, he should basically deal the same amount of damage as usual. But we'll also fill Singed's biggest requirement, being very tanky.

The ACTUAL optimal build

First we'll figure out what runes we'll use. I recommend this page:

Marks: Hybrid penetration marks are stronger in lane than Magic penetration marks, and since we're not building early AP the magic penetration marks take longer to outscale them. I recommend using a combination of them against ranged champions(which you can see on the page). Against melee champions you should always go full hybrid pen. A big amount of Singed's early game damage actually comes from auto-attacks.

Seals: I prefer armor per level but flat armor definitely has its place. I'd go health per level if the enemy team is very high on magic damage.

Glyphs: Magic resistance per level 99% of the time. Cooldown reduction per level or flat/scaling AP if you don't need magic resistance.

Quints: Movement speed quints are good on singed, and they synergise very well with our build. If you have Ghost or Flash Ability power quints can be useful, mostly for cheesing people. If you don't have smite/teleport against something very gay, then health regeneration can be worth it.

The masteries are pretty self-explanatory. Strength of the Ages is better than Grasp of the Undying if you're just farming in lane. But if you don't have Grasp of the Undying against someone who does you automatically lose lane if they play it right. Strength of the Ages can be taken against something like Quinn. Deathfire Touch has some potential for Singed but even with a close-to fulltank build it shouldn't be worth it. Grasp of the Undying > Thunderlord's Decree . Thunderlord's Decree is ok though, and can be worth it if you're cheesing with ignite.

For summoner spells i always go Teleport and combine it with Exhaust, Ignite or Smite. Exhaust is generally the best option, but Ignite can be used for cheesing against champions such as Jax. I generally go Smite against ranged champions and get a Hunter's Talisman, since it gives you more options for gold. Runic echoes is very good in those matchups and decent overall.

Zz'rot portal is the most important part of this build. It's always my first item, even before runic echoes when i have smite. It's the reason to why we don't need Ghost or Flash.

So far I've used these items:

Prio 1:
Zz'Rot Portal

Prio 2:
Boots of Swiftness Mercury's Treads Ninja Tabi(alacrity upgrade)
Possible to sell at endgame for a different item but you will need Dead Man's Plate.

Prio 3:
Liandry's Torment

Prio 4:
Dead Man's Plate Banner of Command Randuin's Omen

Prio 5:
Spirit Visage Thornmail

Prio 6:
Righteous Glory Sterak's Gage Banshee's Veil Rylai's Crystal Scepter Abyssal Mask Guardian Angel