This guide explains how to farm large titanite in Dark Souls II: Scholar of the First Sin.
How to Farm Large Titanite
First of All
Head over to Majula and join the covenant of champions.
This will allow you to keep killing the tough enemy over and over again with no de spawn.
Head over to the undead refurge bonfire. Also known as the Huntsmens corpse.
Continue on the forwards path until you reach the cave area. It's like just near the bonfire.
Pull out your bow and shoot the butterfly things as they will give you toxic. There's a second one on the side.
These bugs do damage over time.
Once the butterfly's are dead jump onto the shell looking platforms and you'll be able to see your target the giant frog. If you desire you can use magic or your bow but i just melee it.
Either way you gotta kill the frog so keep picking away at it's health. There's also a weak torch enemy on the ground.
Once you killed it the drop will be on the ground so pick it up.
You always get three shards per frog.
There's a hidden wall inside the arena with the frog!
Since you can only get out by either dieing or using the elevator chain thing.
I would recommend just jumping into the pit.
Repeat for as long as you want!
As long as you're in the covenant of champions the frog wont go.