Hi mates.Do you think this book can be used in d20 system?Is there enough fluff?

Yes.

thanks mate!!

But you will get easier, faster, smoother roleplaying opportunities and experiences if used the the core rulebook. Genesys not a micro tactical miniatures game pretending to be a rollplaying game like d20 is. (This is not biased statement. If It was biased, this would be include bad things about d20)

Hmm, were it not for the Runes, you could almost use vanilla 5E...

1 hour ago, Lorne said:

Hmm, were it not for the Runes, you could almost use vanilla 5E...

I am doing that exact thing!

As you correctly said, the runebound shards are an issue, so my solution is: instead of learning new spells by copying them into his spellbook, a wizard learns new spells by acquiring and studying new runebound shards!

Admittedly it puts a handicap on wizards, but it's enough of a twist that two of my players have risen to the challenge.

Other magic-using classes are allowed in RoT.

I plan to have weapons and armours with multiple slots that can "accept" runes, so a weapon can have multiple properties by being enchanted with multiple runes, like in the Dragon Age computer game.

The playable races can easily find their equivalent or proxy in 5E, even the dragon hybrid.

The fluff is not detailed enough, but there are plenty of tantalising plot hooks. I am running the game sandbox style, with the Runebound board game map and information from RoT. I put red pins all over the map and read the description for each location from the book to my players, and when they heard about the rune-marked obelisks in the Ashen Hills, they said: let's go there - the one pin I did not have a module ready for!

So to OP, the answer for me is a resounding YES.

I currently use the setting for my D&D 3.5 campaign. Personally, I think I was pretty thorough. Can check it out here: https://www.scabard.com/pbs/campaign/235523