Zardnaar
Legend
For whatever reason there seems to be an idea that you can't clone 4E using the existing OGL rules. You can use the 5E engine (or 3E even) to clone any edition of D&D you like. You won't have something 100% but you can probably get it to 90% and you can probably remove the treadmill effect of 4E or use a blend of that and the 5E system to pull it off. For example your proficiency bonus could be 5E's or the 4E half level thing which would top out at +10 by level 20.
You would also have to translate the 4E round structure into a 5E equivalent, and probably go with 3 HD at level 1. Obviously you would have to rewrite the monsters into a more 5E format but you could use 4E abilities on it. Same thing if you wanted to do AD&D 3E, you could bring back old school energy drain etc and rewrite the classes, monsters etc.
One big difference is if you can convert 5E action into a move or bonus action a'la 4E. Its a bad idea in 5E but if you rewrote all the bonus action stuff in 5E into 4E equivalents it could work.
5E also have things like At will and daily abilities and pseudo encounter abilities with the short rest mechanic. Xanathars has actual encounter abilities in it under a different name. The Warlock also has a very 4E feel to it at least in terms of a template. It would not be hard to turn its invocations and spells into 4E powers or even stick with 5Es approach. You could also use it as a template to rewrite into other classes. After that you just need to plug in whatever it is from 4E that you miss, micro feats its weapon system etc.
The same applies for making your own system or cloning 3.X or B/X or AD&D although you might want to stretch the numbers a bit (half level to proficiency). Then you can just plug in 3E or OSR weapons. Using 5E fxes the number problems 3E and 4E has, if you like that aspect of them though you can still use them but in 4E case you might want to change them a bit due to GSL. Things like xp tables can be tweaked- Pathfinder offers 3 xp tables (fast, medium slow), or you can add a number such as 1001, 2001, 4001, 8001 on the xp tables.
Obviously some work required, my experiment is slowly plodding along. Often its just easier to houserule than make your own.
You would also have to translate the 4E round structure into a 5E equivalent, and probably go with 3 HD at level 1. Obviously you would have to rewrite the monsters into a more 5E format but you could use 4E abilities on it. Same thing if you wanted to do AD&D 3E, you could bring back old school energy drain etc and rewrite the classes, monsters etc.
One big difference is if you can convert 5E action into a move or bonus action a'la 4E. Its a bad idea in 5E but if you rewrote all the bonus action stuff in 5E into 4E equivalents it could work.
5E also have things like At will and daily abilities and pseudo encounter abilities with the short rest mechanic. Xanathars has actual encounter abilities in it under a different name. The Warlock also has a very 4E feel to it at least in terms of a template. It would not be hard to turn its invocations and spells into 4E powers or even stick with 5Es approach. You could also use it as a template to rewrite into other classes. After that you just need to plug in whatever it is from 4E that you miss, micro feats its weapon system etc.
The same applies for making your own system or cloning 3.X or B/X or AD&D although you might want to stretch the numbers a bit (half level to proficiency). Then you can just plug in 3E or OSR weapons. Using 5E fxes the number problems 3E and 4E has, if you like that aspect of them though you can still use them but in 4E case you might want to change them a bit due to GSL. Things like xp tables can be tweaked- Pathfinder offers 3 xp tables (fast, medium slow), or you can add a number such as 1001, 2001, 4001, 8001 on the xp tables.
Obviously some work required, my experiment is slowly plodding along. Often its just easier to houserule than make your own.
