Introduction
Heyo o/
I'm Lin, a *very* casual Leg Legend player and avid Syndra enthusiast on the EUNE server.
I fell in love with Syndra the moment I saw her but I've always hated mid lane, so the most logical solution (to me) was to take her support.

In any case, let's get started with the actual build.

Starting info

Why Syndra?
She's cool. Done.

Jokes aside, she actually brings a lot of utility to the team (which makes her a great support choice in my opinion), has high range poke and her burst damage is unmatched.

As for cons, I'd say that she's easy to punish, very squishy and has no mobility what-so-ever. Her only form of safety is her E and *maybe* the slow provided by her W.

In lane
In lane, you should focus on harrassing the enemy ADC. One combo that I feel works most of the time is Q>E>AA>W. It allows you to proc Electrocute and it will also scare the enemy ADC away, so they won't focus that much on attacking you.

When you get to level 6, killing lane opponents is rather easy. Just poke until you think it's okay to go all in, and once you land your stun, they're yours.

Try not to overextend though, or the enemy jungler *will* gank you. It's very easy to get carried away since you're a huge lane bully.

Rest of the game
Try to finish your mythic item, boots and Void Staff, then move on to Zhonya's for some protection. After that, finish your Tear of The Goddess so you can get the bonus Ability Haste.

Focus on placing wards in all the important places. And punish squishy targets who overextend or wander in the jungle.

Conclusion
While this isn't the most serious build, it's actually helped me win quite a lot of games.

Laters o/