This all will be based on my oppinon. You may have different oppinions on these and its fine, feel free to write them below.
PS. It will be possible pretty long read.
Alrigh. I would start personaly with Orders as they will be quick.
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Personally only order i use is Blind hunt when there is last guy in ARB and he is nowhere to be see, either he is AFK on the border of map, space climbing or just back on air field. For me this is most usefull order for me. Im sure that some order can be used also as AAA or Antimech, but personally i dont use them. But, if you have a booster on, the orders are effected by them. So if you activate correct order at correct time with a big SL booser, you can also get a lot SL.
Next one are wagers.
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Form me, the most usefull wagers are destory 5 and 10 units wager as all i need in GRB is either get 3 or 5 kill. Both ground and air kill counts to it and you dont need to win the battle. even if you loose and have the kill needed, you will go to next stage. So easy SL.
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Then there is a Best squad. I think only wager which reward was nerf as it used to be 500K and now only 250k and for best result you need 3 other people that will play with you for like 1,5 - 2 hr for 10 games to winish the wager.
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Next is the wager that is pretty much impossible to do and for some reason in exist in 2 forms. Shor and long. The Mission maker wager where you need to get a Missin maker reward. For that you need to get First and Last kill of the game. Unless you are extremly lucky you will not get it. I think i got it like 3 times for the 6 years im playing this game.
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Thunderer and Unstoppable wagers are pretty much same. Both can be done but with these wagers you are competing with your team (and maybe even with enemy team, not sure.) For Ground you need to have most kills on your team, but need to be 6 and more kills to get the stage. For Air, you need to have most kills pretty much, or destroy most AI targets. So it is possible to do few stages of it, not sure if fully.
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Hero of the sky wager. Almost same as previous wager, but this one is only for Air and you need to have most kills that are not a AI. So actual players. With me not being great in air, i dont do this one at all.
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Wing breaker is also for the air only, where you need 5 or more kill. Players kill, so one again, no AI. And like previos wagers, im not great in air so im not doing it.
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Wingman wager is a wager where all you need is to have the most assistance in game. Not sure if only a assistance where you shoot the enemy and not kill it and someone else kill it will count or if a scout assistances count also. If yes, this is a best wager for a ligh tank players who love to scout. Didnt try it yet myself so i dont know if scouting counts.
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Battle victory wager. A wager that heavilly depends on how good your team is. And lately it seems that teams are getting worse and worse. Dont know if its just my bad luck for teams or not. But still…im sure if you are lucky, you can get few stages, but not sure if its possible to complete.
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And for last, wagers that newer players will never see and probalby didnt even know about it. Officer golden battle wager and Commander golder battle wager. Where you dont earn SL but GE. Gaijin “removed” these wagers from games, dont know why, but if you still have them in inventory like me, you can still do them. There are 2 part that you need to do. 1st is to get kills. For Officer you only need 1 kill and for Commander you need 3 kill. And then there is the second part. Same as battle victory wager, you need to win those game. And as metioned before, that heavily depends on your team. And these wagers you can only fail 3 times so you can loose it and not even get 1st stage due to your luck on team. And with 20 and 25 stages that you need to complete? Where toget to next wager you need to play 3 battles get it. I would say these wagers are pretty much impossible to complete, as the mission maker wager.
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And that its. That all. What i would love if i could exchangne orders and wager either for 1k SL of some WB for the shop that would be nice…or for wager to exchage 3 same wager for 1 different one.
Hope that this helped someone. And if you have any tips to any of the wagers or orders, feel free to write them here.