Lunar Flare Build
Best choice if the enemy team lineup is lacking of mobility. At least one tank should be present in the enemy team to finish the quest quickly.

Sentinal
Good choice if you need to stay more backline. Aggressive lineups of the enemy team with great mobility allows you to support your team from a safer position.

Hunter's Mark
The most aggressive build. You need to be often in closer range to the enemy team. Choose that build if you have a strong frontline in your own team and if you are able to stay in the middle of the pack.


NOTE:
This a just a recommendation. Always try to adjust builds to your own preferences. Especially ults should be chosen situational and in regards of own and enemy lineup. Keep that in mind.