So I decided to post my Fiddle guide on Mobafire.. It's my first guide, but this is how I play him.

1. 3v3

- At first blood, You can Flash behind an enemy, Exhaust him, and then just drain him and let your team do the rest. That will probably grant you your first blood.

- Later on when you have your Terrify, You can just run to them, Fear them, Drain them, and during the drain if the Fear effect shall vanish, you can just use your exhaust if it's ready. It won't break your Drain ability, and you will have to glory of finishing your complete drain, which does a lot of damage.

- The Ultimate. You can use your Ultimate to get through walls in the middle of 3 enemies, exhaust if needed, Fear & drain the most or the least vulnerable enemy, your pick. Also, if you have your Flash spell ready, you can use ur ultimate through a wall, if the enemies are too far away, just flash closer and apply the usual combo.

2. 5v5

I don't play a lot of 5v5 tbh, but There are a couple of things I know that are possible as Fiddle.

- When you have a ward at Baron's, you can time your ulti to steal the baron buff. Also Apply your Drain ability on the Almighty Baron Nashor to almost guarantee a steal. Then just Flash back to the cliff you were standing on (behind Baron) to a safe get away. If you do not manage to get away, the rest of your team still got the buff, so it's a win-win situation.

- If you have time, you should use your ulti + fear + drain, and if you're high enough, after drain you should throw that Dark Wind after them if they got health left. Also remember to use your Dark wind in team fights because it also silences the enemies, bouncing off 5 targets!

- If you're playing solo mid, You might want to change either flash or exhaust to teleport. Pretty much your pick. I tend to keep Flash though for numerous reasons.

3. General

- Note that if Played correctly, There is no champ that can win a 1v1 against you, unless they got a Twisted Fate with a stun card ready.

- Although Fiddlesticks has got a lot of spell vamp with his drain, It can be difficult to 1v2 enemies, if they're champions can stun or silence you.

- If you aren't familiar with the term Spell Vamp, It's like Life Steal for AP (= Ability Power) aka. Mage type champions.

Hope you liked my very first guide, Feel free to Leave criticism, hate, or love down under. =)
(I'm still a bit unfamiliar with how this editing stuff works, but I hope this is ok =) )