Depends entirely on what you want to get out of the game. It’s possible to play without spending money, but progress is slower and you may find yourself having to discard covers because you don’t have the HP to roster them. Nature of the beast.
First, aside from winning isos, and buying them, what is the quickest way to build up on them?
Deadpool’s Daily. Depending on roster diversity and strength, you could clear anywhere from 500 ISO (if you don’t have covered/trained 2* characters yet) to 5200 ISO (earn two tacos, pull unneeded 3* covers from both, complete Big Enchilada and earn a cover you don’t need from that).
Depending on how you’re defining “winning,” Lightning Round and Simulator play may also qualify.
Second, how does versus work? Every time I click on an event, I don’t fight like in pop. I am only a to click on the names of the opponent and see the roster.
Not entirely sure what you’re asking here. If you’re asking how to play a versus fight, click the event, then when it loads, click a node and select “fight.” If you’re asking how it works, it’s not true head-to-head play. Rather, you’re taking your roster against that of another player, with the AI driving the bus for that player. The characters you see are based on, someone else mentioned recently, the last team that player won a PVP fight with (unless you’re retaliating, then it’s the team they beat you with).
Third, huge dilemma, especially since I don’t know which are good or crap characters to keep or toss. I have read many post but still need some help. Below is what I have and also waiting to be recruited.
Depends on how you’re playing! I’ve been saying for a while that a number of the characters who get crapped on hereabouts, it isn’t that they’re bad characters, it’s that they aren’t useful to high-end PVP players. There are a number of characters I see get run down who I either quite enjoy using or wish I had. My comments on your roster, one by one:
3* Magneto classic 1y/1r lvl 43
Quickly becoming a favorite of mine. His red is inexpensive and, at higher levels, can do some damage. His yellow isn’t quite as fuck-you as Falcon’s purple, but is still useful, especially when paired with a tile strengthener.
3* Beast classic 1b/1y lvl 43
Beast is an interesting guy. His powers all work together - blue and yellow both create friendly blue tiles, which his green turns into improved team damage - but he doesn’t have an obvious “fit” to me. I don’t know with whom he really pairs well. He’s on my bench for that reason - I have him, I like him in theory, but even at 3/4/5 I haven’t figured out how to integrate him, so I haven’t really trained him.
3* Black Widow grey suit 1g lvl 40
Her purple is a fantastic green battery, and I think I like it as a battery more than the reworked 2* Magneto purple. Pairing her up with Rocket and Groot makes for lots and lots of Blammo. Her red does some nice board shake as well, and that’s useful to me because my Groot teams don’t often have an active red ability. Her green, while hurtful AND capable of team damage, is on the expensive side, so there’s that. But GSBW was the first Black Widow variant I actively wanted on my roster.
3* Bullseye classic 1 lvl 40
Worth keeping, I think. His purple is a nice foil to Daken or other tile generators, but can also be paired with a tile generator of your own. His black passive feeds into his purple, in that if he takes someone down, he creates more tiles for his purple to play with, and his green allows him to potentially set up critical matches without being able to change tile color the way other characters do. Mine is 2/0/4 at the moment, and as soon as I get a black cover for him I think he’s going to be a regular for me.
3* Doctor Doom classic 1p lvl 40
Doom’s purple will fuck shit up. His blue is a nice blue-denial ability against Daken, and feeds his black, which creates attack tiles. One of two characters in the game I originally started building because of how much I hated to face him, and the more I use him, the more I appreciate him.
3* Storm Mohawk 1p lvl 40
One of those I see getting run down all over the place, but I actually like her. Hailstorm will chew through enemies quickly, especially with two applications on the board. That her yellow eats team-up tiles makes her a poor partner for Groot, but that and her green give her some board shake to go with Hailstorm. Her green also gives her the ability, potentially, to erase enemy tiles you can’t otherwise match off. Solid mid-tier 3*, IMO. Worth having, not a “bubble candidate” if you’re in need of roster space, but there are better characters.
1* Iron Man model 35 4/4/4 lvl 40
Worth having around long-term if only for Deadpool’s Daily Quest and its 1* fight. His red and yellow are reasonably cheap and he has enough HP to hold his own in that fight.
2* Captain Marvel Ms Marvel 2/2/1 lvl 31
A mainstay of my DDQ team. She tanks for 2* Magneto and 2* Storm while they do the damage. I don’t use her in PVP or PVE unless she’s boosted these days, but I use her at every opportunity in DDQ. Solid 2*.
2* Daken Dark avenge 1/2/1 lvl 25
I don’t know. It’s weird. He’s annoying to fight against, but I never felt compelled to build a 2* Daken. I’d start and then get a 3* character I wanted and sell him for the roster space. His 3* variant, though, I’ve built and kept. I see him used frequently with 2* Wolverine in PVP, so if you plan to play PVP at the 2* level, he’s probably worth keeping.
1* Black Widow modern 5/5 lvl 23
Power-wise, I feel like she’s kind of OP for a 1*. She’ll steal your AP all the damn time and stuns like that on a 1* is…dammitsomuch. Health-wise, I don’t know that she can really hold her own on a 2* or stronger team. She can be nice to have as a team-up generator for alliance members, though. I got rid of her when I started getting 2* in quantity.
2* Moonstone dark avengers 1/1 lvl 17
Her red will ruin your whole day. Her purple can be situationally useful, but can also be manipulated to do damage. Control shift isn’t quite as useful as it used to be, but it’s no longer anywhere near as expensive, either. Definitely worth keeping, and somebody I’d build on my own roster if not for constant 3* that make me drool like Homer wanting donuts.
2* Thor marvel now 1r/1g lvl 17
Early mainstay of my roster. Beef, yellow was a nice green battery, and his green does some things. For where you’re at, definitely a keeper. If and when you transition, you’ll want his 3* variant.
2* Captain America modern 1b lvl 15
Took me a while to really appreciate 2* Captain America, but at 5 covers, his blue and red are a thing of beauty. I never really gave him the attention he deserved until the first Ultron event. After that I spent, like, a week putting every ISO I had into him to get him to 94. Keeper.
1* Hawkeye classic 5/5 lvl 11
I really don’t care for 1* Hawkeye. He’s useful for the prologue and that’s about it, IMO.
1* Storm modern 4/5/2 lvl 7
Your 1* Storm gives you an idea of what to expect from 3* Storm, if you want to build her. Do you like what 1* does for you? Do you want to see that, only more so? Keep 3* Storm. If you don’t like 1*'s power build, you probably won’t like 3*.
1* Juggernaut classic 5/3 lvl 15
Worth keeping if you’re willing to devote the roster spot. Possibly above Iron Man if you’re only going to carry one 1* long-term, but it’s worth noting that his headbutt, while ouchy, also hurts him. So…
He scales stupidly well in the Balance of Power event if you play PVP long-term at all.
4* Carnage Cletus Kasady 1r lvl 70
The first 4* I don’t actually want for myself. The fact that he hurts his own team makes him a big ol’ “nope” for me. Thing you have to be aware of with him is that if you aren’t playing at a high level in either PVP or PVE, it’ll be a long time before you cover him, especially if you aren’t spending money.
3* Cyclops Uncanny x-men 1gray lvl 40
I like Cyclops. Unconventional color spread for his powers. His red moves the board and his yellow is a nice red battery. He can do some damage grown up, if you’re willing to devote resources to him.
3* Gamora Guardians of the Galaxy 1r lvl 40
Another of the characters I like who catches some grief. Her green does team damage and stuns 2/3 of the enemy team. Her red is inexpensive straight damage. Her black is where it gets tricky. She has to carry the board for it to be useful. If she doesn’t carry the board, she’s kind of neutered. Flip a coin on that one. I like her, but your mileage may vary.
3* Vision Android Avengers 1y lvl 40
His powers are probably the most complicated set we’ve seen yet. The blue and yellow modify the red so that it behaves differently depending on what tile he has on the board. Blue turns his red to team damage, yellow converts enemy tiles. He’s not a fire-and-forget character, for sure, and I think that might be why he has some detractors. Situationally useful, but the fact that his blue and yellow modify the red means that he needs covers before he can BE situationally useful. At a single cover, he’s worth keeping only if you can justify the roster spot long-term.
2* Magneto Marvel now 1p/2r lvl 23
Mainstay of my DDQ team. My 3* roster has grown significantly in strength just since the last Ultron event in large part because of my 2* team of Magneto, Storm and Ms. Marvel. Definite keeper, IMO.
2* Ares Dark Avenger 1r/1y lvl 17
Once I covered and trained Ares, he displaced Thor as the centerpiece of my early 2* roster. He’s beefy, when he hits an enemy their mother feels it, and he has a team-damage move (red). Drawback: yellow self-harms (although can heal most of that back) and his green feeds green to the enemy, so you have to be careful how you use him. He’s still one of my favorite 2*, all told.
2* Wolverine Astonishing x-men 1r/1y lvl 17
His red will leave a mark if he’s got 5 covers and is boosted for an event. His green makes him a nice partner for your 2* Daken, feeding him strike tiles to convert with Daken’s blue. His yellow allows you to go longer without using a health pack, since he can heal back up to 50% strength. A mainstay of my 2* team in those days. Keeper.
Here are the few awaiting to be recruited and for some I gave only 2 days left.
2* Storm classic lvl 15 multiple
Keeper. Despite having a number of level 94 2*, I wasn’t able to consistently earn covers in DDQ until I started using Magneto’s purple to feed Storm blues for stuns in waves 2/4. Worth it for that alone.
2* Hawkeye modern lvl 15 multiple
Situationally useful! If you can trigger a crit with him up, he’ll fuck up the enemy’s whole day. Not a lot of health, though, so you need somebody to hide him behind.
1* Iron Man model 35 multiple lvl
Sounds like you’re undecided which power to train for his 13th cover? I went 5/3/5; the red is reasonably cheap and does close to 1k damage at 5 covers, which ain’t bad for a 1*. His blue stuns for 3 turns at 5 covers. It’s the most overpriced power in the game if I’m not mistaken, so 5/5/3 might be a more cost-effective variant, but for a 1*, I felt like 3 covers in yellow was “good enough.”
2* Bullseye dark avengers purple lvl 15
His recent third power addition has me exploring him. Not sure how I feel about him yet.
2* Human torch Johnny storm red lvl 15
Since his red destroys two red tiles on use, and generates AP, the net cost is 6 red, not 8. Solid damage for the cost. His green, powered up and protected from matches, is a thing of beauty. Like, even better than Ares if you fire it at 30 green AP. Doesn’t do as much damage up-front, but does more long-term and doesn’t feed the enemy greens.
1* Yelena Bulova dark avengers purple 3X lvl 1
Her “I’m turning your special tiles into crits to hit you in the face with” is infuriating, but not enough for me to devote a roster spot to her. 
2* Black Widow original lvl 15 multiple
Like Doom, annoying enough to face (my god, the AP steal and heals) that I eventually built one of my own, but I haven’t trained her to 94. If you play PVP, she will make your opponents curse your name when they attack you.
Again thank you. Hope to grab better understanding of the game with time. Currently do not have enough HP to buy more rosters.
And I guess that’s where we get into the “spend money on the game” discussion. I’ve spent maybe $30 over the months picking up roster spots, never spending more than $5 at a time. I don’t buy tokens, until recently I never bought PVP shields (and only started once I could mostly or completely finance their purchase with the HP earned in PVP), and I don’t spend real money on tokens. If you’re going to spend money on the game at all, your best value is probably going to be for roster spots. If you choose to be totally F2P, the roster crunch is going to be an ongoing thing for you unless you get super lucky with DDQ tacos and consistently finish high in PVP (with as little shielding as possible) and/or PVE.
