1-bar builds have existed before oakensoul but you’re probably not going to get “ez mode” arenas nor get into endgame. Oakensoul is what makes 1-bar builds as strong as they are. You’d either have to get oakensoul or learn 2-bar.
PC/NA Dungeoneer (Tank/DPS/Heal), Trialist (DPS/Tank/Heal), and amateur Battlegrounder (DPS) with a passion for The Elder Scrolls lore
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Warden Healer - Arcanist Healer - Warden Brittleden - Stamarc - Sorc Tank - Necro Tank - Templar Tank - Arcanist Tank
1-bar builds have existed before oakensoul but you’re probably not going to get “ez mode” arenas nor get into endgame. Oakensoul is what makes 1-bar builds as strong as they are. You’d either have to get oakensoul or learn 2-bar.
If you have the gold for spell power potions or the time to farm the ingredients, I would recommend Magicka Templar.
If not, definitely Stamina Arcanist. That one has all the tools and power to offset your ... peculiar prerequisites.
Arcanist can also 1.5 bar with recuperative treatise and cruxweaver armor on the backbar. Just cast them pre fight and both will be up for 30s. That is pretty good.
But seriously, fighting one bar without Oakensoul is equivalent to roping your right arm to your left knee and wearing a blindfold over your eyes, ears and nose.
PVE I'll give you two options, the new option and the old option.
1. Old Option. This is templar. Just go magplar, grab yourself War Maiden's and Deadly (you can replace one with Pillars if you want). If you don't use a mythic as you stated, then you have a couple monster helm options. You can go either Nerien'eth or Kjalnar's Nightmare if you're using War Maidens, or you can use Zaan, Stormfist, or Selene if you're using Pillars. You can go dual wield with Precise and Nirnhoned, or a lightning staff.
Use Puncturing Sweep, Solar Flare, Ritual of Retribution, Radiant Glory, Channeled Focus/Barbed Trap depending on your sustain. You can use Templar's Crescent Sweep ult, or something else you do you. As the guy said above, spell power pots make this build work if you don't use Oakensoul, which means ya gotta level up Alchemy.
It's not as good as it used to be, what with the nerfs to Sweeps and Backlash (as you can see since this build doesn't even have backlash on it anymore), and the change to DOTS lowering the damage of Ritual. But it's still solid.
2. New Option. This is Arcanist. Stam Arcanist. Pillar's of Nirn + Deadly, and Kjalnar's Nightmare or Zaan (preferably you'd use the Velothi'ur Mage amulet, but it's a mythic). Lightning staff is probably best here.
Use Flail, Fatecarver (either morph, depends on your preference), Fulminating Rune, Barbed Trap, Elemental Blockade, Languid Eye ult. On your backbar, just slot Tome Bearer's Inspiration, either morph doesn't matter since you're just using it to passively get the bonus on your front bar, you don't need to swap bars to use this. You'll need crit potions with this build. If you don't mind swapping to your back bar for one skill, put barbed trap on your backbar and slot Camo hunter on the front bar, if you don't wanna use pots.
Solo-ability is lower than magplar, since you wanna spam beam and flail is where your hp comes from. But it's also solid. If you have the ability to get mythics, then go grab the Pale Order ring. this makes the Arcanist basically unkillable in solo content.
Like others stated,there's no good option anymore for onebar anything,since mythics are a thing.You can do overland/solo arenas pretty much onebar no plus/mythics,will jsut take longer,but doable but not easy at all.Magic based is the way to got especially for arenas,so MagSorc,prob altmer or dunmer,war maiden/new moon acolyte and either chudan for resistance,or diff combos for pen,crit or recovery.I use that setup onebar and could solo most things,jsut once I got oakensoul it became tons easier.In the end,you either need to get gifted High Isle and Greymoor (can't remember if another dlc is needed),so you can atleast get oakensoul,or deal with twobar or lower dps.