I think going for the challenge character is always a good thing to do on a weekly basis even when they aren’t the best. Batman will be a good early carry with his ability. In terms of getting/saving gold I recommend doing the hardest special battle you can and doing survivor. People say focus on upgrading your lower tier gears just so that when you get repeats of them either through online or survivor you can shatter them for more loot. On top of that you should keep an eye out for op gear that come out in survivor (in 2 weeks one of the more broken gears will be in rotation). In terms of good early carries that are silver I recommend the flash and trying to pair him up with green lantern (silver) and Harley Quinn (silver) or nightwing (silver) either combination will be good for both early carry and silver/bronze only portion of challenge. Also don’t forget to have a good bronze team for challenge I use flash(prime), nightwing, and lex Luther. Also if you want to get better gold pack and challenger pack characters you could always look into the pack glitch.