So after being confused by the Avengers rules, I decided to take off the glass and see how they worked. Before I go into many details, it appears that the game is actually complete including the mini wizard mode (attack the helicarrier) and the wizard mode (battle for earth). As of v1.2, there is no more 6 ball multiball. Even the wizard mode is only 4 balls. However, you can add-a-ball to get to 5 and stack the MB to get to 6.
There are stages to each avenger:
1) Qualify the avenger
2) Collect the avenger
3) Requalify the avenger
4) Complete the avenger in an avenger vs avenger dual
Qualify The Avenger
To qualify each Avenger, you must start his mode by shooting him. In most cases this is accomplished by simply shooting him enough times to start his mode by lighting his row of inserts. Except Thor and Hulk which require knocking down their drop targets a number of times. Each of these qualifies the Avenger. For Hulk, he is qualified when you light the green arrow.
Collect the Avenger
To collect each avenger, first qualify the avenger then shoot the additional shots on the screen to collect the avenger. Once the avenger is collected, his insert is flashing. Once qualified, there is no time limit to collect the avenger. It also does not reset on ball drain. There are often a lot of shots to collect the avengers. For example, for Black Widow, you have to shoot the ramp 10 more times to collect each letter of "black widow"!. For Hawkeye, you must spell his name. For captain america, you must hit 100 pop bumper hits. The DMD tells you what to do. Also, all this stuff stacks with multiballs as well as collecting other avengers. (I did not test if it stacks during Loki multiball - update: Loki mb locks out the other shots and they resume afterwards). It also does not stack once an avenger is collected as described below.
Complete the Avenger
Once you collect an avenger, it will be flashing. At this point, qualify the avenger again, and you will start a multiball. For all the avengers, this is a 2 ball multiball and is a "battle" with another avenger. This mode is exclusive and locks out everything else, until the avenger is completed or you drain one of your balls losing the battle. However, once the avenger is completed whether the multiball is over or not, you can resume collecting other avengers or starting other multiballs - even with the 2 ball running. If you start another multiball after collecting an avenger you simply get an additional ball. In fact, this is a fantastic rule. After collecting an avenger, you get another ball into play until you drain it. I love this rule! So collecting an avenger then starting hulk without draining means Hulk will be a 5 ball MB, Loki a 4 ball, etc. While running the collect avenger multiball, there will be specific shots indicated on the DMD and indicated to shoot by lanes flashing on the PF. It's pretty obvious what to do.
If you fail to collect the avenger (your ball drains ending your multiball before you make the needed amount of shots), you must requalify the avenger. But once requalified, you immediately resume your multiball battle. The battles all have progression so if your MB had 10 shots required and you made 6, you only have 4 more to get the avenger completed.
During any of the MB's if you manage to light Nick Fury and hit him, the first time you hit him is usually an add-a-ball which restarts your ball saver.
I will not go into detail as to what the mini and wizard modes do. I purposely let them drain and ended them to not spoil anything.
So my opinion of the rules, the rules are fantastic. I love the stacking nature of the ruleset as well as the progression. The game is pretty difficult. It will be achievable to get to the mini wizard mode (about as hard as say battle royale on spiderman). It will be very difficult to get to the wizard mode as you have to survive long enough to actually beat each avenger's multiball. Not to mention that the shots are all very tight. It's great. I love the way that the modes never time out. I love the way that you can strategize a hulk multiball to collect another avenger, I love the fact that you keep your added ball after completing an avenger.
Also the sounds in this game are awesome. I think it's some of the best sound track in any pinball game. Every one of the voice actors did a great job. I think Thor is the Magneto voice actor from Xmen.
So far, the only bug I found while playing was that at one point, extra ball was lit but the light was not on. The DMD indicated as such, the callout was there to get the extra ball, and the shot gave me the extra ball.