From what I've seen, this is the least popular mode in Battleborn, but it's honestly not half bad. In Meltdown, your team's objective is to shepherd your minions to the enemy's side of the map, where they'll sacrifice themselves to give your team points. Larger minions are worth more points. When you're halfway there, the furnace that your minions have to reach is placed even deeper in the enemy's side of the map. The first team to 500 points wins.
These are the tips that I think most people can benefit from hearing. Meltdown is an odd gamemode, so it has to be played in creative ways.
1. Choose Anyone That Minions Despise
Meltdown is pretty much all about the minions. Players play a role, of course. But you need to know what role that is. Killing enemies doesn't mean anything if none of your minions reach their furnace. You should choose characters that excel in taking down Meltdown's minions, like Reyna (Plasma Pulse melts their Overshield) or Marquis (Just snipe the poor guys to death). Work with your team to figure out what your strategy is, and choose your characters based on that.
2. Build Shard-Generating Items
Like Capture, Meltdown has strategic build nodes scattered around its maps. But unlike Capture, Meltdown allows you to summon a very large minion with your shards, and this large minion is worth far more points than any other minion if it reaches the enemy furnace. Get an early-on Shard-Generating item for your Loadout, then spend the rest on Turrets, Accelerators, but most importantly, those large, Elite minions.
3. Know When to Split Up or Group Up
Meltdown's unique objective requires teams to split up into separate lanes. This is unavoidable. But you're all part of a team, and teams perform their best when working together. When you know that your allies need help at the opposite lane, clear up any minions you can without staying far too long, and go help them out. Communicate with your team and tell them when you're spawning an Elite minion, then all of you should shepherd it to the furnace together. The enemy team will have the choice of either trying to stop the minion or your team, and it's honestly a lose-lose for them either way. Even better, have a team mate spawn an Elite minion for the other lane, and have your best duo and trio escort both the minions to the furnace in each lane. Splitting up has to happen in Meltdown, but it's not like grouping back up temporarily is an awful idea.
4. Learn Minion's Critical Points
You should at least get a grasp of the general area in which a minion will take extra damage. This is especially true for the Shepherd minions that spawn with each wave; somewhere on their underside in the back is their weak point. It's much better to not waste time, and simply unleash basic attacks all over that critical point. Of course, focus down Shepherd minions before anything else in each wave (except Elite bots), as they're worth the most points to the enemy if they reach your furnace. Focusing them down is even easier when you know what kills them. Elite bots that you spawn with shards have their weak point in the blue exhaust hole on their back.
5. Distract Enemies from Minions
When it's just you and another enemy in a lane, for instance, sometimes they'll completely ignore you and attack your minions. While this is negative for you in general, it's a perfect opportunity to punish them and trade their life for your minions'. Alternatively, sometimes enemies will completely focus you and ignore your minions. This is good. Lead them away, fighting back when possible, and stall for as long as you can. Your endgoal should always be getting your minions to sacrifice themselves, no matter the cost. And if you do this right:
6. You Can Recall
Once again, I remind all of you: You have the ability to recall back to your base to refill your health. Just press B, stand still, and watch the pretty animation. Watching an ally slowly regain health at a Supply Station as fast as a lethargic turtle is infuriating. If you absolutely need to heal, don't waste yours and your allies' time by standing at a Supply Station (those should only be for a bit of quick health gain), just press the B button. Please.
You'll never play on any Meltdown map that's not Paradise. Accept it.