There are four more Relics that you can collect at this point:
Except for the Mace, where you need to have the Boots to get it, the quests can be completed in any order that you want.
Once you have retrieved the Cuirass, you will start hearing rumors of someone trying to reestablish the Knights of the Nine and NPCs will begin making their way to the Priory wanting to join. Eventually there will be eight (counting you, that makes nine members of the Knights of the Nine). Whether you want to allow them to join is up to you. They will help you fight Umaril during the last quest, but if they die they will be replaced by a generic "Knight of the Nine". Aside from that and the fact that they will follow you after you complete the questline, they are just kind of there for color.
Remember, please that you cannot equip any of these items if you have 2 or more points of Infamy. If that happens, you'll need to do the Pilgrimage quest again in order to reduce it.
Objective: retrieve the Gauntlets of the Crusader from the Chapel of Stendarr in Chorrol.
Sir Casimir is the quest-giver. Sir Casimir accidentally slew a beggar in Stendarr's Chapel. The Gauntlets fell off of his hands and could not be picked up again. They remain in the Chapel to the present day.
Travel to Chorrol and speak to Areldur to learn about a descendent of Sir Casimir, Kellen, who is in the living quarters of the Chapel. After speaking to both of them, go talk to Areldur again to find out that Kellen's curse can only be removed if someone is willing to pray at the altar in the Chapel and take the curse on themselves. When you pray at the altar, you will receive the "Lay Hands" lesser power, which you can then use to cure Kellen and remove the curse from the Gauntlets. The downside of doing this is that your Fatigue will be damaged by 5 points (semi-permanently, although this is sometimes a little buggy and may not kick in). Once you have removed the curse, you can pick up the Gauntlets and be on your way.
Don't forget to read Notes on Racial Phylogeny in the chest next to Kellen's bed. It permanently boosts your Restoration skill by one point.
You will get your 5 points of Fatigue back when you complete the "Blessing of Talos" quest.
Objective: retrieve the Shield of the Crusader from Fort Bulwark
Sir Henrik is the quest-giver. He stored the Shield of the Crusader at Fort Bulwark for safekeeping. Although construction had not been completed by the time that he died, he is pretty sure that it was eventually completed and that the Shield is quite safe. He urges you to remain true to the teachings of Julianos. Since Julianos is the god of Wisdom and Logic, expect puzzles and traps galore.
Fort Bulwark is inhabited by Conjurers, who are also looking for the Shield. Too bad that your quest is to retrieve an item with a "Spell Reflection" enchantment since that would be awfully handy about now. If you are at least Level 10 and would like to take a side-trip, you can complete Peryite's Daedric Quest to get "Spell Breaker" (30% Spell Reflection). Otherwise, "abandon all hope, ye who enter here" (not really, but I've always wanted to put that in a quest description).
Conjurers, unfortunately, do not like the dark, so they have lit up most of the place pretty well. Sneaks will be working at a disadvantage almost the whole way through. And since we're dealing with Conjurers here, keep in mind that reinforcements are only a spell-cast away for these guys, so you want to hit as hard as you can from the outset and take 'em down quickly. "Silence" would be a good thing if you can get your hands on it.
Because this is Trap and Puzzle City, you'll need to make sure that you explore everything you can since many places will be inaccessible unless you do something in another part of the fort. In spite of this, the way forward is fairly linear. In the northwest section of the fort you will find a note telling you that they have managed to get past the lower gate and that you should "make note of the candles on the wall" if you want to pass through, too. When you get past the drawbridges, you'll find the candles next to a little pressure plate puzzle. Note which side of the path the candles are on and how many of them there are. Then, from the candles, count across that many pressure plates and step on the plates in sequence to unlock the gate on the far side (the order as you are going toward the gate is left, center, right, left).
The second section of the fort is not much better. You'll find Sir Thedret in a prison area. He was searching for the Shield, too, when he was ambushed and captured by the Conjurers (the Shield seems to be a popular Relic). The Conjurers plan to dispose of him in a "manner most painful", according to the note you find across the hall from his cell. If you free him, he will pass along a clue that he withheld from the Conjurers: "When the eyes of the guardians are upon you, Julianos will show you his favor." After which he will beat feet out of there. You'll find him at the Priory later. If you don't talk to him, he will get out on his own without giving you the clue. The "guardians" to which the clue refers are four statues around a symbol of Julianos in front of a statue of Julianos. Once you dispose of the Conjurers in the area, use the handle on each statue so that they are looking toward the symbol in the center. When they are, the fires around Julianos' statue will flare up and go out and a doorway will open. That's your way into the next area.
The third area is the real puzzle. Since the Conjurers never managed to get this far, you won't find any enemies. In the big room are eight guardian statues facing the wall. Each has a stone chest in front of them. There is a raised platform in the center where you will find a ninth stone chest with a pressure plate in front of it. This chest, however, is not empty. It contains a single item from the following list:
If you stand on the pressure plate in front of the ninth chest when you take items from the chest, look at the eight statues. One of them will show an item for a brief time. That's the item that needs to go into the chest to activate that guardian statue. When the proper item is placed in the proper chest, the chest will start glowing and that statue will turn around and face into the room. If an improper item is placed in the chest, it simply disappears and will reappear in the ninth chest later. Put all eight items into their proper chests and the back wall will open, letting you access the vault where the Shield is stored. There are no other traps (that I've found) in the last room, so just pick up the Shield and whatever other goodies are laying around and you're done.
Sir Thedret will eventually show up at the Priory. He's the only NPC that will automatically join the Knights and he is essential until the questline is complete. After completing the questline, Sergius Turrianus (a blacksmith) will show up in the basement of the Priory, having heard from Sir Thedret that you needed one. Turrianus won't have anything to sell, but will repair equipment at normal rates. When you hit Expert in Mercantile, you can invest 500 gold with him and he'll be able to buy some of your stuff.
Objective: retireve the Boots of the Crusader from the Shrine of Kynareth
Sir Juncan is the quest-giver. He will direct you to the Shrine of Kynareth, a little west of the Ring Road going around the Imperial City (there will not be a marker on your map - follow your compass).
This quest is pretty quick and dirty. Travel to the Shrine and speak to Avita Vesnia about the Boots. She will direct you to the Grove of Trials (follow your compass again) where you will need to undergo testing by Kynareth. The short version is that a Forest Guardian (a Brown Bear) will come out of the woods and beat on you. Don't fight back (although blocking and healing yourself is quite fine). Alternatively, a "Calm" spell effect (like from the Helm of the Crusader [hint, hint]) will cause him to quit attacking and complete the quest. When the bear heads back to the woods to do what ever it is that bears do in the woods, a doorway will open, revealing the entrance to Kynareth's Grotto. There are two Spriggans inside who will do nothing (killing them will get you a point of Infamy), so you can just walk up, take the Boots, and be done with it.
A short while later, Avita Vesnia will come to the Priory and ask to join the Knights of the Nine.
Objective: retrieve the Mace of the Crusader from the Chapel of Zenithar in Leyawiin
Sir Ralvas is the quest-giver. He asks you to go to to Chapel of Zenithar in Leyawiin and complete the quest that he failed because his faith was not strong enough. Actually, his faith was probably just fine. His problem was that he didn't have the Boots of the Crusader, which you will need to complete the quest.
Travel to Leyawiin and enter the Chapel. My best recommendation is to do this quest between midnight and 6 AM for reasons that will become clear later. The time is completely irrelevant to the quest, but it can have an effect on the aftermath.
You will be approached by Carodus Oholin, who will ask if you are the person who is reforming the Knights of the Nine. He tells you that he tried to retrieve the Mace, but was unable to do so and stayed on to guard it. He tells you to to into the Undercroft and pray at the tomb of Saint Kaladas if you'd like to try to retrieve it yourself.
When you pray at Kaladas' tomb, you will be transported to a nether realm of some sort. You can see the Mace on a tower directly across a dark gulf from you. I suppose that this is an homage of sorts to Indiana Jones and the Last Crusade ("Only in the leap from the lion's head will he prove his worth"). Tossing pebbles into the air in front of you won't solve the puzzle, though. I haven't tried a super-boosted Acrobatics skill combined with the Boots of Springheel Jak, but no amount of leaping has gotten me across the gulf to the Mace. After a few failed attempts, your Journal will tell you that you should go look for other Relics and a solution will present itself.
The solution is to equip the Boots of the Crusader. When you do this, you will see a glowing path leading to the tower with the Mace and it's just a matter of walking over and picking it up. Once you do, you will be teleported back to the Chapel. Quest done? Hardly.
When you reenter the chapel, you'll find a fight going on between whoever is in the chapel and some new critters called "Aurorans" (they're leveled Daedra for all intents and purposes). Carodus Oholin is quite capable of holding his own against these guys, as are some of the priests. However, you can find any number of other NPCs in the Chapel, depending upon what time of day you go. So if you'd like to reduce the chances of losing an important NPC to the Auroran attack, retrieve the mace between midnight and 6 AM when there won't be anyone else in the chapel except the priests (who will be replaced if they are killed) and Carodus Oholin.
Each of the Aurorans will have a Daedra Heart, might have a soul gem or another type of gem/jewelry, and should have a leveled Ayleid Battle Axe. If you're going to take the Axes, retrieve them quickly because they tend to disappear after the fighting is done.
After the fighting is over, Carodus Oholin will ask if he can join the Knights of the Nine.