What is an isekai? An isekai is where a character is transported to an unfamiliar world. Often, but not always, their former experience or the transferring process gives them some advantage over the inhabitants of their new locale. 

How do we isekai? The eternal question posed since time immemorial. Every isekai comes with its own in universe stats and certainly you can tailor an RPG system to fit it. But everyone has their own favorite isekai and I wanted to make a RPG that could apply regardless.

You just can't hope to use stats and levels in a standard system. The range of powers and variety of attributes is too wide and varied. You have to use Approaches. Describe your action using your in universe stats, equipment, magic, cheats etc. If there is no risk and uncertainty, it just happens. Otherwise, figure out the difficulty and roll the most fitting approach.

Brave for direct, forceful action. Shadow for cunning, deceptive ones. And Sage for calm, almost oblivious actions. And of course RAGE for when the characters get serious, edgy and aggressive, 

From Sexy Battle Wizards, I modified the resolution system and most of the stress system.

From Lumen, I take the very important approaches and that sense of power and freedom that it brings.

From Forged in the Dark, clocks and from Lady Blackbird, the generous energy system that powers the CHEATS.

Of interest, if a player fail a roll and your highest roll is less than your RAGE(SBW stress modified) then everyone fails. Your RAGE costs everyone the encounter and the enemy achieves their objective. Isekais aren't meant to be balanced but the characters don't need to get what they want. They can be clumsy or hot headed and make mistakes. They don't necessarily get hurt in this system, rather they fail in a spectacular, encounter ending way.

As it stands the document as it stands is best served for small groups. Larger groups don't necessarily require bigger clocks. Rather the amounts of attempts could be the same between large and small groups.