I’m going to lay out the game philosophy behind how we decided to do Tribulation Mode because I think it’s going to be misunderstood by a lot of folks.
First, here’s a playthrough of two games that are in the style we are doing.
https://www.youtube.com/watch?v=22oTEDa2Rxk
https://www.youtube.com/watch?v=bAH2KMiscqY
Some people aren’t aware that this genre exists, and SAB TM may be their first exposure to it. We took a creative risk by going in this direction with it rather than the standard make-enemies-hit-harder-and-give-you-less-health approach that most games use to ramp up difficulty. That would have been very easy and very safe. (And probably more popular.) But we never do anything the easy or safe way. 
The thing that makes this approach tricky is that on its surface, it seems to be bad design because it is intrinsically unfair. What fans of the genre understand is that there is a depth there that comes from a really interesting dynamic in the communication between the designer and the player that doesn’t exist in other games. It’s hard to articulate, but I would say it’s something like friendly pranking. There’s great pleasure to be had in finding ways to outwit a prankster. And that can’t happen unless you have a prankster. And that’s what the designer provides. People who don’t ‘get’ this kind of game see it like the designer is trolling out of cruelty, and so they read malicious intent into the invisible insta-kills. But that’s just not the case. It’s simply a specific kind of content made for a specific kind of player who wants in on the pranks. Yes, raging is part of the process. In fact, I rage at myself when I play TM all the time!
And the thing about how it is unfair: yes, it is. However there is a deep satisfaction to be had in overcoming in an unfair fight. In these games your only real power is tenacity. And besides, it’s only unfair in the short feedback loops. (Here’s some information on feedback loops in game design: ) http://www.jorisdormans.nl/machinations/wiki/index.php?title=Feedback_Analysis_and_Recurrent_Patterns
But the longer (and more substantive) feedback loop is a process of learning how the designer thinks. Discovering that style and finding how to navigate the level better as a result. The first lesson is this: the most obvious easy way will most likely kill you. The harder, more circuitous rout will probably be the way to go. This creates a joy of discovery and overcoming that few other genres can provide. But it is an acquired taste.
Another commonality among games in the genre (which I’m not aware of having a name yet… let me know if you’ve heard of one) is that lives are extremely cheap, and you blow through them. Lives are like HP in an RPG or ammo in an FPS. You go in EXPECTING to lose a LOT. If you interpret losing a life as “failure” then you will have a miserable time. It would be like feeling like you “fail” when you take damage in a turn based role playing game. Instead, if you see every death as another learning experience, you’ll have a much better time. Kind of like the way your armor rating increases when you take damage in Skyrim. So part of preparing for a TM run, you’ll be ‘leveling up’ your ‘life meter’ by collecting as many lives and Continue Coins as you can.
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