I have no problem admitting when I'm wrong, and in the case of Sub Zero's tag battle, I was. I didn't fully understand the mechanics of the battle, and assumed the assists were random. I should've recalled the last couple of NRS games, because these are the same mechanics that were in MKX IIRC.
You face a boss in teams of 3, each of you fights him 1 by 1, and as the boss gets weaker, their own assists get stronger. This is as true as it ever was. However, you're supposed to play this battle in windowed mode, because YOU the players control the assists. While P1 is fighting, P2 and P3 may use their assists to help P1, and so on.
For this battle, the following assists were given:
P1: Special forces carpet bomb, super armor, and a heart that drops to the ground and you gotta walk over to pick up
P2: Mileena's sais, Juggle Kombat which makes the enemy ragdoll for bigger combos, Super Armor
P3: Instant heal, Hydro assists (tidal wave), and a gift of ice pick up that gives you armor against being frozen for a few seconds
Not only do these pickups make the fight beatable, they make it fun too. Even the ridiculous phase 3. Here's a video of me and 2 randoms beating it. It's muted because the first player didn't understand how to use assists, like I once did not, and I spent much of the game telling him to do so on the mic.
So to reiterate, I was wrong. This fight isn't one of the bad ones. Good job making it fun NRS.