The best team is the one listed earlier- SoJ, BAM. Fennec, IG-11, and Kuill. Both LV and Rey are walks in the park to beat and the other GLs (minus Kenobi) are doable provided you have at least equal relic levels
Key things to remember are Fennec is your main damage dealer, SoJ's basic is your backup damage attack- it does more damage than either of his other moves, and finally modding BAM for survivability can make a huge difference especially if you're trying to go in with low relic levels, although if you're going in with a r3 Fennec you're not going to have an easy time
Against LV you need to get the payout off quickly so you can ignore taunt and make Fennec do max damage. Use your AoEs to get there quickly and make sure to use BAM's damage immunity when needed to keep the team alive. Use Fennec's special when available on Lord Vader to get those armor shred stacks on there. Wear down the teammates killing Darth Vader ASAP if he's there. And remember when you use SoJ's first special it spreads tenacity up to the team which boosts Fennec's offense pretty heavily
Against Rey target Rey herself. Once you get the payout off you can take her out pretty quickly with Fennec but remember of course Rey's usual mechanics. You need to make sure you can rattle off BAM's damage immunity once Rey goes into ultimate or when a whirlwind comes up
