THIS IS A TROLL BUILD. As such, do not attempt to use this build unless you want to **** around. Do not judge this guide as if it were a competitive build, because it isn't. Note the "troll" tag up at the top. You have been warned.

I know you may be thinking to yourself, WTF? AD/AS Singed? YOU MUST BE CRAZY!

SILENCE! CRINGED DOES NOT TOLERATE YOUR FOOLISH DOUBT!

Inspired by Crittlesticks and how ridiculously fast he is, I decided that Singed could serve a similar function. Everything Singed does is based on mobility, so why not make him as mobile as possible?

This in turn led me to look at the movement speed items and determine that most of them also contributed to attack speed and critical strikes. And thus, CRINGED was born!

I take Critical chance Seals and Marks because CRINGED loves making BIG RED NUMBERS appear over the heads of SQUISHIES. And the sooner you can start CRITTING SQUISHIES the better!
For Glyphs I take Attack Speed Glyphs so as to make the BIG RED NUMBERS appear even FASTER over the heads of SQUISHIES.
And finally, I take Movement Speed Quintessences, because NOBODY escapes from CRINGED. EVER.

On a serious note, if you want to build something semi-legitimate, replace Attack speed Glyphs with MR per level and replace Crit Chance Seals with Flat Armor Seals.

As CRINGED you only need OFFENSIVE masteries related to ATTACK DAMAGE AND SPEED because then the BIG RED NUMBERS will appear over the heads of SQUISHIES SO FAST.
And the rest you put in the utility tree, Mana for your FLINGING so you can FLING the SQUISHIES and then CRIT THEM TO DEATH. Take two points in LESS TIME SPENT DEAD so you can spend MORE time FLINGING AND CRITTING SQUISHIES. And finally, take speed, because NOBODY ESCAPES FROM CRINGED. EVER.
Also you want the Offense mastery related to Ghost and Exhaust.

ALL but ONE of these items gives you Movement Speed. THIS IS ESSENTIAL, AS NOBODY ESCAPES FROM CRINGED. EVER.

You get Brawler's Gloves early so you can begin CRITTING SQUISHIES from the beginning of the game. 2 Health Potions helps too.

Next, you upgrade your Gloves into an AVARICE BLADE so you can GET MORE GOLD so you can CRIT SQUISHIES TO DEATH even sooner!

Next, CRINGED DEMANDS MORE MOVEMENT SPEED so you must get him boots. Those boots must then become SUPER BOOTS, because NOBODY ESCAPES FROM CRINGED. EVER.

Next you must obtain double Zeal, and then the occurrence of BIG RED NUMBERS over the heads of SQUISHIES will INCREASE TENFOLD!

It is at this point that your opponents will truly fear you, as they will NEVER ESCAPE, and they will watch their PUNY LIFE BAR dwindle into NOTHINGNESS, all while BIG RED NUMBERS scroll by!

Next, upgrade your Zeals into a Phantom Dancer and a Trinity Force, because nothing makes SQUISHIES CRIT THEIR PANTS like being slowed by a CRINGED who ZOOMS AROUND THE MAP LIKE HE OWNS IT.

After you have successfully made SQUISHIES CRIT THEIR PANTS, it is time to become tanky, as those fools will undoubtedly be focusing you in the next team fight. With that in mind, you must obtain FORCE OF NATURE and FROZEN HEART, as these two items together will make you INVINCIBLE and UNCATCHABLE.

Finally, upgrade your trusty Avarice Blade into a Youmuu's Ghostblade, and ACTIVATE it so you can CHASE DOWN THE SQUISHIES, and FLING THEM, and then CRIT THEM TO DEATH. All while pressing Shift+3.

The first skill you must take is FLING. This allows you to FLING SQUISHIES into your tower for FUN and PROFIT.

Next take a point each in Poison and Mega Adhesive. This will allow you to run in front of your unfortunate target, poisoning them in between hits.

After obtaining your ultimate, max Mega Adhesive first as that will scale the best, forcing your victims to wallow in puddles of glue while you CRIT THEM TO DEATH.

Next max your Poison Trail as you will need its straight damage without any AP built. Finally, max Fling to round out your skill set.

THERE IS NO CHOICE ON GHOST. IT IS NOT NEGOTIABLE. IT MAKES YOU FAST AND UNESCAPABLE.

If, however, you wish to take something other than Exhaust (but why would you?), Surge is the only other acceptable item. You do not need any other summoner spells, because CRINGED is not a support, he is an AD CARRY with a FLINGING addiction. Make sure you have the Mastery for increasing Ghost, as it boost from 20% MS to 35% movement speed. That is a lot.

With all the items I have shown you to build, CRINGED reaches a very high MS, making it almost impossible to escape unless you are Master Yi or Rammus. CRINGED starts at Base MS of 320. With Boots of Swiftness, he gains 90 MS for 410. Applying the 4.5% increase from Quints, you get 426 MS. That's pretty dang good at that point in the game. Once you obtain your first Zeal, that shoots up to 452. The second Zeal bumps it up again to 478. Once you turn your Zeals into Phantom Dancer and Trinity Force, your Movement Speed becomes 500. Adding Force of Nature to that gives you 523 MS, and if you activate Youmuu's Ghostblade on top of that, you get 564 MS for 4 seconds. If you really want to go all out, though, activating Insanity Potion on top of Ghost on top of Youmuu's active, combined with all your other items, you get 699 Movement Speed for 4 seconds. On top of this, your Attack speed is up by 50% for those 4 seconds. In other words, between these insane speed boosts and the 75% slow from your Mega Adhesive, YOU CAN GO WHERE YOU WANT AND NOBODY WILL ESCAPE. Or if you're trying to escape, NOBODY WILL CATCH YOU.

Just make sure to bind your /L or Shift+3 to a fun key/mouse button and spam it constantly.

CRINGED DEMANDS THAT YOU GET OUT THERE AND FLING SQUISHIES AND CRIT THEM TO DEATH.