I will concede, the spell does what it says. I wanted to continue discussing, but reflected I would never limit Tensor's Transformation, so why would I place a limit on Divine Power.
I will leave my below comment:
The reality is the spell caps at level 20 in the Players Handbook and the SRD is incorrect.
Base Attack Bonus (BAB) is often misunderstood. BAB only accumulates up to level 20 and does not increase afterwards. Epic level characters 21+ receive a different bonus called Epic Attack Bonus, not to be confused with Base Attack Bonus received from levels 1-20.
This means that a character that took 20 levels of Rogue (BAB 15) and then 20 levels of Fighter (Epic Attack Bonus +10) would have an attack bonus of +25 and three attacks/round (attack are calculated of BAB only)!
Whereas a character that took 20 levels of Fighter (BAB+20) then 20 lvls rogue (Epic attack bonus +10) would have +30 to hit and four attacks a round!
The character that took the rogue levels first would need Divine Power to get four attacks a round and a +30 to hit. This is a great spell for Rogues, Clerics and anyone who doesn't qualify for the extra attacks a round.
I was sure I found the reference in the Players Handbook but it has been a while since this came up. I do not have a PHB here, so thank you for the exact wording. Our group derived the answer from the Epic Level book. It says that Base attack bonus does not increase after character level 20.
Epic Attack Bonus: Similarly, your base attack bonus does not increase
after our character level reaches 20th. However, you do receive a
cumulative +1 epic bonus on all attacks at every odd-numbered level
beyond 20th, as shown on Table 1–1: Epic Save and Epic Attack Bonuses.
Any time feat, prestige class, or other rule refers to your base
attack bonus (except for gaining additional attacks), use the sum of
your base attack bonus and epic attack bonus.
The DM could rule a few ways on Divine Power.
- The BAB limit is 20, so the Divine Power caps at 20. I think this is the most logical interpretation.
- Divine Power references Base Attack Bonus and your new BAB and Epic Attack Bonus would be 40.
- A 40th level character who casts Divine Power gets a BAB of 40! This is awesome because it would definitely stack with your Epic Attack bonus! Making your attack bonus +40 for Divine Power, and +10 for 20 levels of Epic giving you a +50 Attack Bonus.
Each interpretation could be defended. I agree with the first interpretation because the Epic Level book opens by saying BAB caps at 20 and Epic Attack Bonus is different.
The second interpretation makes Divine Power an excellent spell at Epic levels...maybe more than excellent depending on how high your epic level game goes. It would be good with the persistent spell feat (24 hour duration).
The third interpretation, that Divine Power BAB would stack with Epic Attack Bonus is silly...