Wondrous Item, very rare
This book contains coordination and balance exercises, and its words are charged with magic. If you spend 48 hours over a period of 6 days or fewer studying the book’s contents and practicing its guidelines, your Dexterity increases by 2, to a maximum of 30. The manual then loses its magic but regains it in a century.
Notes: Bonus: Dexterity Score, Bonus: Ability Score Maximum, Buff
what about a Second Lv artificer warforged
with Artificer Infusions, replicate magic item?
Replicate Magic Items only works for common magic items if not in one of the tables.
I play a drow rogue. They can live several centuries.
While I find the discussion about RAI vs tweets vs updates very interesting, this version of the item literally says "to a maximum of 30." Obviously your DM can change this if they wish to and allow no maximum but it's strange to argue that this item has no limit RAW when it very clearly says it does.
Those comments were made on the original version of this item from the 2014 Dungeon Master's Guide, which actually didn't list an explicit cap on the ability score increase in the magic item description itself. That's why people were arguing about it.
They're still wrong that there's no cap, because both the 2014 and 2024 Player's Handbooks specify that no ability score can ever go higher than 30.
Can I use several manuals of the same stat?
Yes.