From publisher blurb:
Revisions of Origins a is handbook of character options for 5E
This can be used by any group looking for a little more variety in their characters and a few new ideas.
In this volume you will find:
3 new Races:
- Mantiss Warrior
- Half Ogre
2 new base classes:
- Eldritch Assassin: An assassin who gains abilities from a dark pact.
- Bladeheart: A spellcasting swashbuckler that chanells magic with swords.
New options for existing classes:
- Cavalier: A specialist mounted warrior
- Cloud Walker: A monk tradition with movement powers that belongs in the clouds.
- Hidden Blade: A rogue specialising in twin dagger fighting.
New feats and introducing Feat Synergies.
All of which are completely unrelated and not necessarily printed in that order. In my experience when new character options are grouped by theme it produces a volume that benefits one player at the table but fails to inspire others. The unrelated nature of these options allows the whole table to be inspired as the options are as different as the players.
If you have felt stifled by the small range of 5E options, then Rats in the Rain are giving you more options, choices and ideas than you will find anywhere else.