First and foremost - get all your arena champs to 60, fully ascended, with full masteries, and close to all level 16 gear. Anything less is a waste of time.

Secondly, that team won't work. You need either a second (possibly even third) speed booster, or someone to stop them from acting.

Your roster is quite limited. From your options, I would probably go with:

Genbo Lead

Apoth

Khatun

Umbral Enchantress

Make sure that you're tuned properly. One speed boost directly into the other, directly into Umbral A3. Genbo should be geared as a pure glass cannon. No stats other than ATK, CR, and CD. He doesn't need anything else.

Other options to keep in mind, that you can't quite do yet, but you're close:

Ursuga + BEK + Draco/Serris + Seer - very strong nuke combo but requires very good gear as well. All need to be very tanky.

Arbiter (who you clearly don't have yet, I know) + Longbeard + Sinesha + Skullcrown (who you probably don't have yet) - classic blender comp. Very, very effective.

I would go:

genbo, umbral (super fast), serris (2nd), ninja/septimus/kael (last) for now.  Or use HK if really fast  instead of 2 nukers.  Need Umbral to win speed race, so would need all your best speed/perception gear probably.

How are your speeds on those champs now?

My advice for you is Stop trying to build the fastest team out there, cause there will always be someone with a faster team. Probably everytime you hit refresh there will be one.

Building champs that can endure a round or two of attacks, obviously slower, but with crazy amounts of crit damage and defense, can be just as useful as a faster champ attacking first, etc. 

However, it is notably harder to build a successful defense/hybrid style team than it is building the standard speed nuke team, speed boost into speed boost into def down into aoe attack champion to wipe entire team. 

The reason for this is because the game features slightly more attack based champions and speed is the only stat that directly controls who goes first, and if you can win in just your one round of turns then that = faster wins, more medals faster, faster great hall

There also exists the acc/res overcast, for some reason it is and has always been, easier to land a debuff with any given amount of acc then it is/has been to resist a debuff with any given amount of res. I believe if you go to the calculators and type in two matching values for acc+res compare, youll get a higher percentage to land debuff and lower percentage to resist everytime.

(Info from deadwoodjedi and every calculator ive used since march 2021)

Could be wrong somehow so just saying for that imminent post correcting me on this and everything else im telling you

😑

To me, a 33% HP aura is much more useful than a 20-30%speed aura because i already have my champions as fast as i need them with the gear equipped. As long as I know my nuker can one shot the reviver or most of the time, entire team then i know their nuker is atleast as strong as mine, but most likely 20-40% weaker than mine since I survived and won the fight. Build the team around your nuker fast, but focus on stacking crit and crit dmg on your nuker because even though they are slow as s%$# , when they do go they smack hard. 

Defense champions with damage scaling from defense are realistically the only kind of champions you can even use for this type of method, this comes with a small disadvantage compared to attack based champions as far as base crit damage%, and base DEF being marginally smaller in value than am attack champ's ATK stat. 

I would recommend using a VOID defense champion with good multipliers, that Umbral would work nicely. Dont listen to people on here telling you you need acc, you need no acc whatsoever, build her all for damage, crit rate 100, crit damage 180+ shoot for defense above 4500, and attack as high as possible since some defense champs scale damage from defense and attack. Defense is the only stat in this game that serves multiple purposes and controls several mechanics... damage multiplier, damage mitigation, HP effectiveness, survivability...

Ysing void champs as damage dealers also give you the benefit of no weak affinity chance.. 

Build a fast team around your nuker, but focus on crit dmg and defense because once youve built an effective defense style team and tear through gold arena, youll know that youve done what those other speed teams have done without any increase attack bonuses or speed or TM boosts... your guaranteed to have a stronger nuker on your team than any other team if youve made it this far with a comp. There still will be teams that just completely wipe you in the blink of an eye so be prepared for the occasional matchup with a kael that has 300+crit dmg and 4000 ATK with 225 speed. Lol. They are out there

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