Old King Allant is a Boss in Demon Souls.
Allant, driven by a lust for power, became a demon after he made a pact with The Old One. This boss is known as the 'False King' because it is not the REAL Allant. After Allant allied with the Old One, he was given immense power. Using this power, he fashioned a demon made in his own image, made to look like his old self at the height of his power. This demon would lead the demon armies against Boletaria.
Old King Allant is highly resistant to magic and partially resistant to fire. He also is difficult to knock down or stunlock unlike most humanoid-esque enemies.
The Eternal Warrior's Ring is recommended to help keep up stamina. Purely physical weapons with range, such as Spears work best. Magical damage weapons have little effect. You can also use Turpentine if you have the time. A good shield is highly recommended. He has a unique Soulsucker attack at melee range which will actually steal one Soul Level from you, so don't stay too close to him.
You should be constantly backing away with your shield raised unless you are good with your dodges. You need the stamina regain, so don't put your shield up too often. Being close will leave you vulnerable to combo attacks, and his Soulsucker move. When he points his sword straight down into the floor and starts glowing, he is about to execute an area explosion attack. It is possible to outrun, but far better to run up and bash his face in. After you interrupt this attack, immediately roll backwards to avoid his counterattacks.
When he raises his sword at an angle, he is about to rush you. Roll aside and he should miss you entirely. As soon as he stops behind you, turn and smack him once before rolling away again. All other attacks do negligible damage and can be safely absorbed by your shield. If you need to heal, the best time to do it is when he is slowly walking.
Exploiting ranged attack
Old King Allant is made even easier by the fact that he has only two long range attacks.
His rush, which is easily avoided and does negligible damage leaving him wide open after the attack
His explosion attack, which leaves him vunerable for several seconds beforehand.
His shockwaves are also long range, but can be blocked entirely by a decent shield. By keeping your distance Old King Allant becomes quite simple. This strategy also completely eliminates any chance of losing soul levels.
- Ranged Strategy
The White Bow, Sticky Compound Long Bow, or Quality Compound Long Bow will do excellent damage with Heavy Arrows or White Arrows if you have them. The goal here is to stay at a distance while he moves back and forth. With a proper lock on, you can hit him while he walks around, while he charges up a move, and especially while he charges up his glowing sword explosion. If he attempts the explosion once he'll usually attempt it several times in a row, giving you free shots. Never stay within range of his Soulsucker ability. Always dodge to keep your distance if he closes to melee. Be cautious when you heal as he has strange AI (aggressive) when you're at far range. It's fairly easy and safe to whittle him down with a bow.
Super Cheap Ranged Strategy
Wear the Thief's Ring and just after you enter the fog, don't move. You can backstep and he still will not notice you and you get a better view of him. Pull out your bow and manually aim at his head. If the King's life bar is not showing across the bottom of the screen, then he won't attack you. So just hammer him with arrows for the easy victory (tested up to NG+).
As he gets hit with arrows he will slowly take steps back and gets further away from you. If you're doing less than 25 damage, you won't be able to kill him because he will get too far away for you to hit him.
Use Hyper Mode by equipping the Morion Blade and/or Clever Rat's Ring and getting your health below 30%. You will have an easier time with the added attack power from these items.
If you're having trouble doing enough damage before he steps out of arrow range, Rotten Arrows are recommended. It takes approximately 150 arrows to kill him. It's expensive, but extremely effective.
Using a White Bow with about 100 Heavy Arrows should just about kill him, making it a much cheaper way to fight.
At this extreme range, long-range bows (White Bow, Sticky Compound Long Bow) and Light Arrows will usually do the most base damage.
Area of Effect exploit
Equip Soul Ray and Warding only, so that you don't have to constantly search for the spells you want. Make sure you have enough Spices to keep your magic points up. Old Spice being the best choice. Use the Kris Blade, Monk's Head Collar, and a light set of armor that doesn't eat stamina. Wear the Ring of Magical Sharpness with the Cling Ring if you are in Soul Form. The Eternal Warrior's Ring and Ring of Magical Sharpness if not.
Using a bow is really optional for the opening shot, but not really necessary. Cast Warding as soon as the fight starts, and be mindful that it only lasts 40 seconds, so you'll have to recast. Move towards the center of the room and keep him at medium distance. When he charges up his horizontal sword swipe, dive left or right. Keep circling around him until he lifts his sword and looks like he's going to stab the ground. (He makes certain yells when winding up for certain moves. They become pretty obvious after awhile). He will do a rather large and damaging Area of Effect attack. Quickly shoot him with Soul Ray and wait for him to try it again. Usually, he does it around three times. After the third attempt, move back and get ready to recast Warding.
It's imperative that you always keep your camera facing Old King Allant so that you can see what he's doing. Keeping him in the center of the arena, so that you always have an exit to either the stairs or near his throne, in case you aren't close enough to catch his Area of Effect attack.
Equip Warding and Firestorm and make sure to wear Monk's Head Collar, Kris Blade, and Ring of Magical Sharpness for added damage. As soon you enter the room, cast Warding. Rush for the stairs and turn left (or right) immediately after. You should be in a corner. Wait for the king to charge you and as soon as he touches you, cast Firestorm. Kill him in Normal Game with two casts.
Super cheap, Poison Cloud
An easy, yet time-consuming method is to use Poison Cloud. As you enter the fog, wait for king to turn back facing the stair, walk to the top of the stairs while wearing the Thief's Ring. Cast Poison Cloud. Wait until it wears off. His health meter will stop moving, and you'll stop hearing the poison sound. Cast Poison Cloud. You'll need to repeat this six times, so a good deal of patience is required.
- Soulsucker Note
As mentioned above, Old King Allant has a Soulsucker attack that can drain one soul level from you and might kill you at the same time. However, those souls aren't necessarily lost forever. Instead, if you die while fighting Old King Allant any souls that he stole from you will be deposited with the rest of your souls on your bloodstain. This also applies if he steals from you more than once and if he kills you with a different attack. For example, if he stole from you twice and you survived both times, but you died because of his explosion, you can recover the souls for both of those levels. However, if you die again without touching your bloodstain, those souls are then lost forever.
If Old King Allant steals one of your soul levels and you beat him, you do not get back the souls you lost.
- Invasion Glitch
It is reported that when invading in 1-4, it is possible to enter the boss room while the host is fighting.
- Ostrava of Boletaria, his son, was searching for him and after being severely wounded by the demon impersonating his father. Ostrava gave the Mausoleum Key to the Slayer of Demons so that the hero could free Old king Doran and get the legendary sword, Demonbrandt, to kill Allant and save Boletaria.
Has the highest hp of any boss in Demon's Souls.