I was invited into a campaign that is ending by a group of friends, so for me this will likely be a one shot.  I made this character with an eye toward going first, and doing enough damage to tip the scales of battle before it starts.  I see a lot of builds that take a 1 level artificer dip, and were i not making him at a level that gets a feat, I would probably do that (and if the campaign continues, I may take it at level 13.)  All items and feats have been approved/provided by the DM. You can view the character at the link above, but here is my rational in building it.

Ability scores: I rolled for stats (on discord with a bot) 10, 11, 11, 12, 14, 17.  I'm a wizard so INT is priority, I view not getting hit better than taking the damage (and the amulet of Health was given to me) so DEX is second.  Normally, I would go CON here, but I knew I'd have the amulet.  It's metagaming, but oh well.  The rest of the scores are really personal preference.  I knew the party had a high CHA character so I could put an 11 in that, STR an 11 as well, WIS is the 12 for perception and the saves. CON is a 10, because Amulet of Health.

Race: Of course bugbear because the main purpose of this build is using the racial Surprise Attack Surprise Attack To gain more damage on the first round.  The group didn't need a ranger, and the bugbear Gloom Stalker is already a known build. Racial stat boost went into INT for obvious reasons and STR because I'd rather have a +1 to athletics than the charisma skills.

 Feats: War Caster gives the bonus on concentration saves, and opportunity attacks. Alert Is to make sure I go first, even if I didn't know the enemies were there, and Fey Touched gives the last +1 to Int and some nice spells.

Battle plan: My initiative bonus is likely ~16 or 17 (assuming gift of alacrity with an average of 4.5) so I imagine I'll go before everyone.

If there were multiple enemies, say some support minions, I could start with Fireball, and not get the bugbear surprise bonus and do 8d6 (1/2 on save) or up to 11d6 (1/2 on Save) cast at 6th level. Roughly 28(14) or 39(19) damage to each. Or I could start with Steel Wind Strike and deal 6d10 (33) + 2d6 (7) damage for an average of 40 damage on up to five  creatures.  Alternatively I could use Scorching Ray at 2nd level for 2d6 +2d6 (14) damage against 3 creatures, or at 6th level for the same damage against up to 7 creatures. Which I choose would be based on do I have advantage, do they have cover, are they resistant/immune to fire, etc...

If there is only one or two enemies, I think scorching ray is the way to go having them targeted by multiple rays. Casting it as a 6th level spell against 1 target would do 14d6+14d6 (98) assuming all hit, none crit, and no immunities, resistances, or vulnerabilities.

Round two and beyond I'm just a normal Cronurgy Wizard.

Solid build. I'd personally go Bladesinger over Chronurgy. 

Artificer dip is definitely NOT worth it. I also don't know why anyone would ever recommend a 1-level artificer dip because you get nothing for it. With 2 levels you get infuse item and there's some OK synergies with some infusions (particularly weapon infusions and bladesingers, since the infused weapon can be used as a spellcasting focus). 

However, this would mean losing a feat and frankly the feat is better.

Good build, multiclass likely not worth it. At such high level maybe stick with main class to get forcecage, wish (if campaign continues), etc as soon as possible. Noticed the character doesn't have dispel magic prepared, maybe it is all good.

Quote from Eoun >>

Good build, multiclass likely not worth it. At such high level maybe stick with main class to get forcecage, wish (if campaign continues), etc as soon as possible. Noticed the character doesn't have dispel magic prepared, maybe it is all good.

 Thank you, I hadn't even thought about dispel magic

Like the idea.

Steel wind Strike is 200hp if they all hit. Then do another one immediately with Contingency. Gotta say starting init with 400 damage before crits is a hell of an entrance.

Thinking end game 20+ level the gloomstalker also adds Wis to init, so (eventually taking ASI after 20 lvl each time) you’d have +20 on init rolls averaging 15 from d20 and gift of alacrity, assuming +5 for adv from a sentinel shield and you get an average of 40 for INIT. Which is fair smoking …

Scorching ray upcast to 9th does 10 rays or 140 damage so still not as good as steel wind strike.

Thought about a lv3 dip into Ranger gloomstalker with blind fighting style. If someone needs dark vision to see you then you get adv on all those attacks and you can see invisio in 10’ and have 90’ dark vision yourself.

Quote from Estaln >>

Like the idea.

Steel wind Strike is 200hp if they all hit. Then do another one immediately with Contingency. Gotta say starting init with 400 damage before crits is a hell of an entrance.

Thinking end game 20+ level the gloomstalker also adds Wis to init, so (eventually taking ASI after 20 lvl each time) you’d have +20 on init rolls averaging 15 from d20 and gift of alacrity, assuming +5 for adv from a sentinel shield and you get an average of 40 for INIT. Which is fair smoking …

Scorching ray upcast to 9th does 10 rays or 140 damage so still not as good as steel wind strike.

Thought about a lv3 dip into Ranger gloomstalker with blind fighting style. If someone needs dark vision to see you then you get adv on all those attacks and you can see invisio in 10’ and have 90’ dark vision yourself.

 Scorching ray is only better if there are fewer targets since you only get the one attack on each enemy with Steel Wind Strike (up to 5) so if there are only 2 enemies, you can Scorching Ray and still get the same damage total.

Quote from Estaln >>

Steel wind Strike is 200hp if they all hit. Then do another one immediately with Contingency.

 
Steel Wind Strike is useless for Contingency because a Contingency spell must be unable to affect any creature other than yourself in any way. So, since as a Contingency you wouldn't be able to attack any creature, using it for Contingency is a waste.

This is what "The contingent spell takes effect only on you" (from Contingency) means. It can only affect (take effect on) you. 

Thanks for pointing that out ... dang. Saved me from some foolish moments when my DM points it out too, just got to 12th level and about to commission an ivory statuette :)

I'll swap that out with Crown of Stars at higher level, not conc and it adds 4d12 (+2d6) as a BA, just a little sweetner to it all.

I wouldn't do the dip. Chronurgy is good but I personally prefer Evoker (with wall of fire, sickening radiance, fireball, etc, since you can protect party members from it). Gift of alacrity is great.

Quote from Estaln >>

Thanks for pointing that out ... dang. Saved me from some foolish moments when my DM points it out too, just got to 12th level and about to commission an ivory statuette :)

I'll swap that out with Crown of Stars at higher level, not conc and it adds 4d12 (+2d6) as a BA, just a little sweetner to it all.

 
Yeah Contingency is finnicky. But was great for a Bladesinger - setting Haste for when you activate Bladesong. Great for action economy. If a DM let's you mix 'n' match Bladesinging with Mark of Warding Dwarf you're in for a good time. Free Mage Armor, can set Contingency for 5th level Armor of Agathys. Then you can cast Haste and make an attack. All in your first turn. 

Another good Contingency trick is if you have a good spell to cast on yourself from a Magic Item - since you can store those with Contingency too. 

Not 5E and not official yet till the books land in September, but new 4th level (1DND) Conjure Minor Elementals. The big IF is if you get to prep by one round, and cast that first as a surprise action before “kicking the door in”. Other big IF is if it appears in the same format as play test 8.

9th level CME does 12d8 bonus (fire) damage per attack, Bugbear does 2d6 bonus (also fire) per attack in round 1, 8th level scorching ray does 9 bolts. So that’s 4d6+12d8 x 9 for an average if my maths holds up of 612 damage in round 1. Total end game picture as it uses a 9th and an 8th slot up front but imagining the scene when the spell slinger boots in the door to the saloon, quick draws a wand from it’s holster and rattles off a slew of fiery projectiles that wipes out the bandits, then smiles at the hostages and yells CLEAR as he holsters the wand and saunters over to the bar. Did I mention elemental adept - fire with all that, ignore resistances and adds +1 damage per 6d6 on average, maybe about +20 for all those dice.

Reputation building stuff.