Sun Blade is specifically a Longsword, but you could negotiate with your DM.
My recommendation is you swap out one of the Scimitars for a Shortsword. That way, you can crit fish more efficiently with Vex. Beyond that, there are a BUNCH of weapons that are excellent for dealing extra damage. I'm more of a fan of the ones that just give straight attack bonuses, but a lot of the higher-end weapons do still give attack bonuses in addition to the damage bonuses. Depends on the rarity you have available to you.
Curious why you're going with a dual-wield, finesse weapon Barbarian? Is it just for the Light property? Also, if you're tanking, you're never going to succeed in getting your AC up with a dual wielder. Take advantage of the rage damage resistance, get a ton of hit points, and just soak blows.
Having dual wielding and the dancing sword may not give you a second extra attack but potentially it does allow you to take 3 attacks with your light weapons and 1 with a d8 weapon for slightly more damage. Probably better would be a viscous shortsword and a viscous scimitar. Alternating these would give you 2 attacks with a 75% base hit for 3d6 +Dex bonus and 2 attacks at base 95% hit chance for 3d6 +dex bonus damage ( 2(.75 x (10.5 + 4) ) + (2(.95 x (10.5+4)))=49.3 dpr
Having dual wielding and the dancing sword may not give you a second extra attack but potentially it does allow you to take 3 attacks with your light weapons and 1 with a d8 weapon for slightly more damage. Probably better would be a viscous shortsword and a viscous scimitar. Alternating these would give you 2 attacks with a 75% base hit for 3d6 +Dex bonus and 2 attacks at base 95% hit chance for 3d6 +dex bonus damage ( 2(.75 x (10.5 + 4) ) + (2(.95 x (10.5+4)))=49.3 dpr
Even level encounters are assumed to be a 65% chance to hit without exceptional stats or magic items and the DPR calculation for the follow up attack to Vex is ... complicated.
Your follow up attack to your first Vex attack will have advantage 65% of the time, not 75%, and, if it does, will hit 87.75% of the time, not 95%. Crits are close to 10% of the time. Because you are missing 35% of the time with first Vex swing, you will actually have a (65% * 87.75% = 57.0375%) + (35% * 65% = 22.75%) = 79.7875% chance to hit. I suspect that it gets a little higher if you are using Vex for every attack except the Nick attack (at which point the chances reset). If you just attack with Shortswords, your chance to keep the chain going improves and never resets but you lose the Nick attack. However, it may be worth it. With this combo, you should only attack with the Scimitar when for the Nick attack in order to maximize the advantage chain.
Using this DPR Calculator to estimate DPR so that it factors in critical chance without me pulling out my spreadsheet. I got a DPR around 48. It should probably be a little higher than that, but I am not sure by how much. Alternating attacks will probably put you at about 48 DPR and that is pretty accurate. 3 Vex Attacks between 1 Nick attack is going to be the most consistent.
If you are going to do two Rare weapons, I would suggest considering a +2 Shortsword and a Vicious Scimitar, rather than two Vicious weapons. A +2 weapon should put you at a 75% chance to hit. If you hit or need to switch for Nick, switch to the Vicious Weapon. Your chance to hit with the follow up attack becomes (75% * 87.75% = 65.8125%) + (25% * 65% = 16.25%) = 82.0625%. This is going to be about 41 DPR but might be more consistent if you expect to face encounters above your level.
If you don't have an 18 because of the half feats, you may be a little behind the curve and face a 60% chance to hit instead of a 65% (70% with a +2 weapon). If so, you may continue to fall behind until level 16 or you take a standard Attribute Bonus for your feat choice.
Your right that a +2 shortsword is probably better than a viscious shortsword. I was assuming that viscious weapons were +2 weapons.
That explains the 75% chance to hit in your math. The damage will be higher with vicious, but the +2 will help with harder than normal battles. If the role is scything through multiple opponents, they probably won't be even or above the character's level so the vicious is a solid option. If they're regularly facing single higher-level enemies, the +2 will help.
Dancing Sword uses a Bonus Action to attack with, so you wouldn't get any extra attacks from it if you are already using the Dual Wielder feat.
Sun Blade is specifically a Longsword, but you could negotiate with your DM.
My recommendation is you swap out one of the Scimitars for a Shortsword. That way, you can crit fish more efficiently with Vex. Beyond that, there are a BUNCH of weapons that are excellent for dealing extra damage. I'm more of a fan of the ones that just give straight attack bonuses, but a lot of the higher-end weapons do still give attack bonuses in addition to the damage bonuses. Depends on the rarity you have available to you.
Curious why you're going with a dual-wield, finesse weapon Barbarian? Is it just for the Light property? Also, if you're tanking, you're never going to succeed in getting your AC up with a dual wielder. Take advantage of the rage damage resistance, get a ton of hit points, and just soak blows.
Having dual wielding and the dancing sword may not give you a second extra attack but potentially it does allow you to take 3 attacks with your light weapons and 1 with a d8 weapon for slightly more damage. Probably better would be a viscous shortsword and a viscous scimitar. Alternating these would give you 2 attacks with a 75% base hit for 3d6 +Dex bonus and 2 attacks at base 95% hit chance for 3d6 +dex bonus damage ( 2(.75 x (10.5 + 4) ) + (2(.95 x (10.5+4)))=49.3 dpr
Wisea$$ DM and Player since 1979.
Even level encounters are assumed to be a 65% chance to hit without exceptional stats or magic items and the DPR calculation for the follow up attack to Vex is ... complicated.
Your follow up attack to your first Vex attack will have advantage 65% of the time, not 75%, and, if it does, will hit 87.75% of the time, not 95%. Crits are close to 10% of the time. Because you are missing 35% of the time with first Vex swing, you will actually have a (65% * 87.75% = 57.0375%) + (35% * 65% = 22.75%) = 79.7875% chance to hit. I suspect that it gets a little higher if you are using Vex for every attack except the Nick attack (at which point the chances reset). If you just attack with Shortswords, your chance to keep the chain going improves and never resets but you lose the Nick attack. However, it may be worth it. With this combo, you should only attack with the Scimitar when for the Nick attack in order to maximize the advantage chain.
Using this DPR Calculator to estimate DPR so that it factors in critical chance without me pulling out my spreadsheet. I got a DPR around 48. It should probably be a little higher than that, but I am not sure by how much. Alternating attacks will probably put you at about 48 DPR and that is pretty accurate. 3 Vex Attacks between 1 Nick attack is going to be the most consistent.
If you are going to do two Rare weapons, I would suggest considering a +2 Shortsword and a Vicious Scimitar, rather than two Vicious weapons. A +2 weapon should put you at a 75% chance to hit. If you hit or need to switch for Nick, switch to the Vicious Weapon. Your chance to hit with the follow up attack becomes (75% * 87.75% = 65.8125%) + (25% * 65% = 16.25%) = 82.0625%. This is going to be about 41 DPR but might be more consistent if you expect to face encounters above your level.
If you don't have an 18 because of the half feats, you may be a little behind the curve and face a 60% chance to hit instead of a 65% (70% with a +2 weapon). If so, you may continue to fall behind until level 16 or you take a standard Attribute Bonus for your feat choice.
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Your right that a +2 shortsword is probably better than a viscious shortsword. I was assuming that viscious weapons were +2 weapons.
Wisea$$ DM and Player since 1979.
That explains the 75% chance to hit in your math. The damage will be higher with vicious, but the +2 will help with harder than normal battles. If the role is scything through multiple opponents, they probably won't be even or above the character's level so the vicious is a solid option. If they're regularly facing single higher-level enemies, the +2 will help.
How to add Tooltips.
My houserulings.