|This build is mainly for people aiming to +10 Walhart. The nature of Walharts weapon makes him comparable to Legendary Ephraim and Legendary Eirika, a lone horse. However, unlike the two, Walhardt does not have a method of dual phase doubling (Ephraim with his weapon effect, Eirika with her super high speed stat of 39). This build attempts to fix this by making Walhart as speedy as he can be. There are alot of flexible slots in this build, so you can play around with it alot.
Wolf Berg is a cornerstone of this build. With this build he benefits for every stat boost, the +4 speed goes a long way for securing doubles. Atk/Spd Solo 3 is the other cornerstone to this build. Combined with his weapon, Walhart gains 10 extra attack, and more importantly, 10 extra speed. At +10 this bumps him up to 41 speed when away from allies. Any other A slot for this build will make it less consistent, however if you don't have this Solo skill, you can make do with Fury 3.
For the most part, the C slot is flexible, however Even Spd Wave 3 (or Odd Spd Wave 3) is a strong option, giving him more self reliance, it also bumps him up to 47 speed. If you were to run a different C skill, Spd Smoke 3 is the next best thing due to how well it sets him up for enemy phase. If you intend to run him on horse emblem, use whatever horse emblem buff your team needs.
The best seal options are Speed +3 for the obvious speed boost, Darting Stance 3 to make him harder to kill on player phase; even for the fastest of units like Ishtar, Raven Ayra etc. Heavy Blade 3 is good if you use the harder hitting specials. Quick Riposte can also be a solid option, turning fights vs Wary Fighter armors back into speed checks.
The special on this build is can be based mainly on what you choose for the seal slot. If you use a simple Speed +3 seal or Darting Stance 3, you can use any two turn special to guarantee proc in when you double, being Glimmer or Moonbow (even Noontime if you want, his attack can reach high levels to make solid use of it). If you use Heavy Blade 3 however, you may want to use the longer cooldown specials, best options being Bonfire or Ignis for damage, Aether for sustain, or Galeforce for a more fun approach.
The B slot is truly the most flexible slot, most B slots can work for any build. Chill Def 3 is a great budget option that works completely fine, Chill Spd 3 can be good for securing doubles. Renewal 3 is great for longer fights in modes like Grand Conquest. Guard 3 raises his survivability greatly. The movement B slots like Lunge and Hit and Run can make Galeforce builds very interesting. Pass 3 can catch people offguard on arena and aether defense and make it harder for you to bait. Vantage 3 or Desperation 3 messing with attack order can come in clutch at lower hp.
+10 Walhart with Wolf Berg, Atk/Spd Solo, Spd Wave and Speed +3 = 50 speed in optimal conditions. +10 Walhart with Wolf Berg, Atk/Spd Solo, Spd Wave and Darting Stance = 53 speed on enemy phase.