Seath the Scaleless boss strategy
Seath is yet another Boss Fight that is incredibly challenging. After your first encounter, you got a glimpse of what this boss is capable of. Like some of the other Lord Souls, this too has a gimmick. Seath is immortal, and you will do no damage until you shatter the crystal behind the room. This boss is slow and lumbering, but can still do some pretty devastating damage to you.
In terms of patterns, Seath is pretty easy to predict, he has several beams, which then spread spikes in the ground which can cause Curse Damage. This comes in several forms, the first of which is around his torso. Beware, this is unblockable and to dodge it you must run. Seath has another form of this breath attack which hits the immediate horizontal area in front of him - this is pretty simple to get away from, just go behind him on windup.
The last of Seath's breath attacks is far by the most deadly. The dragon is able to have an area of effect-like attack which will push the curse spikes up around him, and is very hard to dodge once caught in it. The tell for this to run back once you see his head come down.
Seath also has some tail whip attacks, the one immediately behind him does a lot of damage and can also cause knockdown. While the other tail swipes will not knock you over, but can cost some serious stamina when defending.
Speaking of which, defending and tanking is our recommended strategy for this particular boss. Whether you get caught in the curse or not, higher poise with your armour will get you out of that bad situation as quickly as possible, and help you avoid getting cursed.
Immediately after entering the arena, ignore Seath and bolt for the immortality crystal behind him. After this is broken, you will be able to do damage to him. We recommend hanging out in front of him until he winds up one of his breath attacks, that windup window will allow you to run behind him and in-between two tails. Then, you will be able to lay on some damage.
With a high poise armour set, the little tail lashes shouldn't distract you to much. When you're up close you want to be dealing as much damage as possible, without missing out on any damage if your weapon is not buffed or two-handed. Once again we recommend two-handing during this fight, as it will make it go a lot quicker, so long as you are able to avoid the other attacks that we discussed above.
He will try to position himself in front of you to breathe a curse attack, but this should not worry you too much as you can continue chasing him and getting stuck between the two legs.
The issue only arises when Seath decides to do his bigger AoE Curse attack, where you will need to back off pretty quickly if you do not want to get fully cursed, this is why we're recommending that you go in full-tank mode.
Since a set like the Stone Set or Havels have a high poise rating, you will actually be able to eat a few of the curse hits and run away, while it's hitting you. This is super useful, especially if you want to avoid getting cursed, which is what happened to us while we wrote this.
If you're looking for more help, our Dark Souls walkthrough and guide can help with all other areas of the game, including the dreadedTaurus Demon, Capra Demon, Ornstein and Smough bosses. Meanwhile, we have explainers on how to access DLC Artorias of the Abyss, the best gift and best class in Dark Souls, Dark Souls' best weapons, Dark Souls Covenants, Dark Souls Estus Flasks locations, Dark Souls Titanite Slab locations and NPC quests including Lautrec of Carim.
Seath is a challenging fight, so we also would recommend wearing the Cursebite Ring in order to make the times where you might not be able to dodge out of the way a little bit more bearable. The last thing you want is your health bar getting halved.
Go in with your most powerful weapons, because Seath has a huge load of HP. Stick behind him and watch out for the AoE attack and you should have it finished off in no time!
Once done, there are three other areas and bosses you must tackle before you can head to the game's final area: