Sandking underpowered?

I disagree him being an underpowered hero. The regen during the sandstorm makes sense to me, I think it would be a nice feature. I don't know if burrowstrike triggering caustic finale is necessary. And your item build is pretty standard. I think it works very well, remembering that he's not a carry, hardly a semi-carry, more of an initiator and a disabler.

Sand King is probably one of my favourite heroes.
if you are going for early kills, and ganks - take the old school build - which is stun stats to level 6. Drop the bracer, and get an urn instead - similar benefits, but with the mana regen and active.
Don't farm with sand king (unless you're a few hundred gold from something core like a blink)
Sand Kings stun is actually very OP - as he is immediately transported, NEXT to a target, compared to the stun of Lion (ranged attack delay, whereas melee is instant), or Nyx - this means, automatically you're hitting the stunned hero (probably twice) before they are able to move. A lot of damage for 1 stun. you can also escape with this skill, or catch up to a juking enemy.. so many uses..
Again try not to farm, just get kills and ganks - you will need coordination, but this the ONLY way to play sand king. your items are fine - it is all you need :p
Core is Aghanims and Veil - you probably won't have many items after this point - your ulti has a decent CD - so it should ALWAYS be on CD.. don't sit in a lane, secure the kills, control the runes (for your mid) and get more kills.. Sandking helps everyone else snowball - it's great!

If you're looking to 'mess around with Sand king' get a midas, and level your caustic finalle. when you 'blink epi' hit a creep immediately, then midas the one next to it (assuming a hero is there as well) that is automatically 2 caustics + epi + stun in the space of half a second. very lols, huge dmg - but silly all the same.. Though I haven't tried it an etheral blade would be funny as well.. (blink/epi - etheral trrrooollololol)

You're gonna want to get Arcane Boots in just about any build you're going for, then your early item will consist of an Urn of Shadows which can be replaced by a Wand if their lane is very spell spammy. Your next main item is a Blink Dagger, if they counter Blink Dagger with a Doombringer Radiance or a Necrolyte then you will want to opt out for a Force Staff, if you're having a hard time you can forget both of them and go for a Drum of Endurance. You'll follow up with a Veil of Discord, which should be picked up before an Aghanim's Sceptre as it grants more damage and provides good defence against physical damage. If you need damage after that you can go Aghanim's Sceptre, if you need defensive ability then you may get a Blade Mail to counter physical foes or a BKB to counter spell damage and the HP will help against HP Removal damage.

That should just about cover it for basic items, if the game is still going on, you may sell your Urn of Shadows or Wand for a luxury item like Shiva's Guard, Heart of Tarrasque, or a Scythe of Vyse.

Situationally you may want to pick up a Necronomicon, Linken's Sphere, Mekanism, or a Pipe of Insight.

allright thanks everybody, this really helped alot.
I'll practice some more and test some diffrent item builds in different conditions.

tho practicing against bots with sandking is lame due to the "instant-dust-buying-bots" whenever a random invisible occurs :P

but anyhow thanks for your time and your thinking capacity ;D