in the comics both John Walker and Lemar Hoskins are both juiced up , like Steve Rodgers was

kind of...........

they both got thier powers from the Power Broker , which was mentioned at the end of the episode

so far in the show , they don't have any super powers

but , I think that will change by the end of the series

here's what I think will happen , not a spoiler , just my thoughts

the bad guys , the Flag Smashers , we'll find out they they have a sympathetic cause , and Sam and Bucky will try and help them out

while John and Lemar will join forces with the Power Broker to try and take them down , , and in return will then get juiced up by the Power Broker

by the end of the series , John will give the shield back to Sam , and John will become US Agent and get his own shield , Lemar will be killed off and John will still be a dick

but , thats just a guess..........

as far as John and Sam being able to toss the shield around like it's a Frisbee , I'm guessing is because the shield is made out of Vibranium which gives it , it's own special characteristics

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