Amber

Reload and Damage together on Amber is a pretty mediocre power 11 build, despite both of them being good stand alone gears to have on Amber. Reload is excellent for prolonged battles against mid range and close range brawlers and enables her to rack up consistent kills against them on her good maps, and damage is great for dealing a lot of damage at once, usually helpful when you know you're either going to die or live depending on if you kill them first, which is typically against assassins and brawlers that outrange her.

Now, on paper this might seem like a versatile build, but it's only the prime build on three of the maps in the power league map pool of brawl pass season 15, those being safe zone, pit stop, and super beach. Now the reason damage reload the best build there is the same for all 3 maps. You aren't going to care if you're low hp after fighting and winning lane or mid successfully, you're going to want to keep on fighting or you're going to want to shoot the safe, due to how these maps tend to leave you in close proximity to other enemies or the safe after your matchup ends. But then, what is the best gear loadout exactly? Well... here's some alternate builds.

Speed and Damage. This build excels in scooping up a single kill against longer ranged enemies when the opportunity arises efficiently. Great on Layer Cake, Hard Rock Mine, Goldarm Gulch, and sometimes Ring of Fire.

Speed and Vision. This build is great at preventing sneak attacks from happening, and this build may be worth using on a confined map when the enemy team holds sandy or Leon. Particularly useful when paired with longer ranged brawlers, especially on Canal Grande, Double Swoosh, and Sneaky Fields, and Crystal Arcade.

Speed and Reload. This build really puts Amber in the drivers seat and allows her to go brrr all over the enemies in an instant on her aggressive maps, as opposed to always needing to recover ammo after winning the matchup with speed and damage, or playing defensively with speed and vision. What sets this build apart from reload and damage is it prevents enemies from being able to escape with their speed gears as effectively, also prevents enemies from running up into your face on a bushy map, and makes it significantly more difficult for long ranged brawlers to hit Amber. What sets this build apart from speed and vision is that it provides enough ammo over time to quite reliably overpower a speedy tank lane and be actually impactful to the match instead of just being strapped of ammo, when the tank respawns after pushing back mid lane. It essentially does the same thing as Reload and Damage, but better; stronger against mid range and long range brawlers, but needs a lot of bushes on the map in order to work. Great build to have on Ring of Fire, Pinhole Punt, Sneaky Fields, and Double Swoosh. Best Build? Could be, it's a very useful loadout for ladder.

Health and Damage is a good build to have on maps where cover is sparse against long ranged, low health brawlers. Reload gear is going to be completely useless in bounty against Piper Tick Nani on shooting star, because there's simply an absence of the need for having a lot of ammo, lack of utility for vision and speed gear, and health enables you to hold out for longer against all matchups. Best build for Shooting Star and Belle's Rock.

Health and Vision. The support Amber build. Pretty much only useful on open maps when Leon or Sandy are used or on Out in the Open, as it allows long range teammates to shoot enemies in that long bush without making you as vulnerable to counterattack from enemies as speed or shield does.

Health and Reload. This is the ultimate lane holding build for open maps against moderately and very tanky brawlers like otis, poco, and carl. Having a health pool which few brawlers can kill in two hits allows her to push forward, run back to heal when needed, and come back with pretty much full health and ammo and maybe even a super with her passive super charge in like 7 seconds, making it great on Dueling Beetles, Open Zone, and pretty useful for Bridge too Far.

Damage and Shield. The "I'm sick and tired of being 3-shot by you and I want to run it down on you" build. Only useful for specific matchups, but due to meta shifts, it kind of just sucks right now, but used to be great against byron squeak and bonnie.

Shield and Reload. The better "I'm sick and tired of being 3-shot by you and I want to run it down on you" build, because it's more rewarding to actually win with reload due to having more ammo to attack whatever comes afterwards and due to it being easier to sustain with more ammo. Occasionally useful on Bridge too Far.

To sum everything up, her best builds for her best maps on ladder are speed+reload and health+reload, but many builds are prevalent in the power league map pool, depending on the map and situation.