I had a lot of fun during these DS TBs facing that challenge - these enemies are no joke. Was fortunate enough to go 4/4 on all the regular character nodes I faced (was locked out of a day 3 node so missed that one totally). I tried various combos throughout, including zDM lead, DK lead (with and without zeta), EP, zDV, Thrawn, and Veers...and swapped a few toons across various teams to test what would work. I have a detailed log with screen shots for waves 3-6 and guidance in general in the link below. There you can see what I used that was effective for ideas.
This thread though I specifically wanted to reach out to those that are in a position of having precious resources or just not having worked with DS much and not sure where to turn. I think what you want to do first is just start with a base of at least one strong team that can get 4/4 throughout .. something to hang the hat on and start building success. My pick for the best F2P / ready-made squad that can take you from day 1 through day 6 confidently would be the following:
- Lead: zDV! TM Removal here is huge as is putting the rebels at speed down - the DoTs also help a lot on these high-health enemies as the battle drags on....and the ability to drop a massive culling blade on someone can't be emphasized enough
- TFP: Huge for the ability block (again, rebel specials are key to contain as noted in guidance link above) and buff block. Buff block is critical for the Hoth Rebel Officer that can gain foresight spam and the soldiers that can gain taunt. TFP also has huge damage and great speed, so he's a great unit to take TM with his constant attacks and do massive damage at the same time.
- EP: Oh boy is EP good here. His shock that prevents buffs and blocks TM is HUGE vs. HROfficer foresight spam, vs. the Rebel Soldier's Taunts, Hoth Rebel Commander TM gain on ally damage, AND vs. the Rebel Pilots 100% TM gain on ally death...and that's not all!!! His bonus shock damage on the basic can remove TM from ALL rebel enemies under a zDV leader!!! This can't be emphasized enough. Additionally, shocked enemies take a 2nd bonus damage. So that's 2x chances to remove TM from a shocked rebel on his basic attack that he isn't even directly attacking. If he attacks a rebel directly that's already shocked, that's 3x damages (the attack, the rebel bonus damage, and the bonus shock damage) and 3x chances to remove TM. He's absolutely punishing vs these Rebels. Further...we all know about the AOE stun...but his offense up really sets Vader up nice for a punishing CB. EP & DV...like peas and carrots....
- GMT: Another absolutely elite character here - crit chance and O down - can't be resisted by rebels. That's critical for pushing down enemy damage. Equally as devastating is his Ultimate Firepower special that removes 50% TM. Launch this early in battle 4/4, but try NOT to use it before that because Tarkin builds up damage for each use of his basic attack and it DOES roll over for each battle. So you can do very heavy AOE damage in 4/4 that removes protection and a lot of health with a nuked-up Tarkin. He does not need a zeta to be effective here.
- Darth Nihilus: This is the only borderline P2W / hard toon here, but I know a lot of F2P / low spend have this guy at 7* or very close since he's been so good for so long and have been working on him. A reasonable substitute would be DT or Boba (assuming not a BH required wave) as each of those 3 ability block or increase cool downs. DN is optimal though and elite tier in DS TB because his cooldown on annihilate rolls over each battle so you can start 4/4 with annihilate ready to go. Even more critically though is his ability to increase cool downs. Remember, the rebel specials are OP - you NEED all those debuffs to stick and not get cleansed away. DN locks all those debuffs in by preventing specials from being used.
To summarize, with this team you will be constantly taking TM and have the enemy covered in the following debuffs: shock, cc down, offense down, buff block, ability block, DoTs, speed down, and tenacity down. That's incredibly potent and is how you control the match. Key however is having those abilities to cleanse / heal all that away under control. This is done by ability blocking/stunning/increasing cool downs.
Elite-Tier F2P Toons Generally:
- Death Trooper (debatable if F2P, but given reaper and overall utility he's a high priority target)
Middle-Tier / Useful F2P Toons Generally:
- Darth Sidious
- Darth Maul (though not as a lead necessarily)
- Kylo Ren
- IG 88 (ability block - a key control tactic in these TB)
- Phasma - solid control skills with speed down and TM gain
- Sun Fac - usable general purpose tank
- B2 SBDroid - dispel and buff block are great skills here
Note: I'm excluding the following toons from consideration for this discussion due to availability or special circumstances like past usefulness of characters (for example, Troopers were bad for so long not many built them up or maybe even farmed them)
- SA / Sith Trooper (long-term farm and gear on late Cantina - technically F2P over the long-term, but not "ready-made" - obscure generic Sith with limited general utility or desirability
- Veers / Snow / Shore / Storm / Magma - again technically F2P - but some are hard to farm and they were terrible for so long no one put resources in to them (not including Shore)
- Nightsisters - 3 P2W expensive toons and were terrible for so long that few built them up
- FO - KRU is P2W and seems critical for FO as a lead in TB for later stages, FOST is a hard farm and needs a zeta, Kylo needs a zeta, FOTP is a fairly hard farm as well. Phasma needs a zeta. Huge zeta investment team with modest return. Definitely not ready-made.
If there are any questions please let me know, I'll try to get an answer from others if I don't know myself.