I'm having some trouble with the Elder Four Horns Quest.

I killed the regular blos, but then I ran out of time on the Black Blos.

I prefer using LS on Diablos, but I can use DS if neccessary. I used Fanatic Dragonwood LS (which they nerfed)

Any suggestions on weapon/strategy?

Use the blango Decimator. slice the tail off and then only attack the tip of the tail. Or when you sonic him, destroy his head.

Bleh, Blango Decimator. I need like one more Whisker or tail. Can't member which. Thanks though.

I never Sonic him, so when should I do it? When he's under ground?

You also have to remember that every hit counts. Just keep chipping away at them it really does more than appears.

Thanks guys, I think I can manage now.

I'm off to kill a Blagonga, then the Blos Slaughter begins. MUAHAHAHAHA

I Used Wyvern Blade "Verde" Against Them Just for The Raw Power

And I Finished with Like 15 Minutes Left (They Don't Wanna Separate)
Just Make Them Stuck at Rocks and CUT THAT Tail off(Annoying Tail Sweep)
Be Sure To Throw A Sonic Bomb When They're Underground And Bomb Them While They're Stuck

quote King of Ice

I Used Wyvern Blade "Verde" Against Them Just for The Raw Power

And I Finished with Like 15 Minutes Left (They Don't Wanna Separate)
Just Make Them Stuck at Rocks and CUT THAT Tail off(Annoying Tail Sweep)
Be Sure To Throw A Sonic Bomb When They're Underground And Bomb Them While They're Stuck

You dont really need to bomb..
But ya, first off cut the tail off. That things a pain.
Sonic when they dive, but DONT when they are in aggro, it wont work.

Use the best blango LS you can make. It really makes the difference.

quote Tadpradel

You dont really need to bomb..

It Never Hurts to Do More Damage
Especially for This Quest

Yeah,Use That Blango Decimator
It's Better Than "Verde" I only used "Verde Cause I was Too Lazy to get The Materials

When They're in Rage Mode don't Throw any Sonic Bombs at them when They're Underground,It Won't Work

(Tad,Already Mentioned That but the Word Aggro is Rather Confusing so I'm Clarifying it)

I beat it with tons of time to spare. Thanks. The Sonic Bombs did wonders. As did the Blango Decimator

you can also try to flash bomb it and when it works just stay under him between his legs so you cannot be hitted by its tail sweep...the hard part about flashing a diablos is when it is in aggro mode because it moves outrageously fast just give yourself a great space before throwing a flash bomb when he is angry hehehehe...personally i dont destroy its horns so it always got stuck on the walls but its just me you can still get horn parts but the chances are a bit more drop...