Also, it is a range 0-2 low mana cost attack, which happens to:
1) Be unavoidable (so no Block or Reverse Attack worries),
2) Do very well against Battle Forges in particular, and
3) Water has no specific weakness against armor equipment items (unlike lightning and fire type attack spells)
The only real downside is that you can't hit flying creatures with it.
So... For my usual spellbooks, I do put in:
1) At least one Teleport for emergencies (4 for my Wizard),
2) Generally 2-4 Dispels, 1-2 Seeking Dispels, and 1-2 Dissolves,
3) Almost always 1-2 Force Push / Wave,
4) One of each Force Hammer and Surging Wave,
5) At least 2 walls (3 or 4 if I can afford the spell book points),
6) Two suits of armor appropriate to the Mage's training,
7) One to (more likely) two Mana Crystals / Flowers
1-2 Decoys,
9) Eagleclaw Boots, and
10) Elemental Cloak (for all but the Necro, who has the Cloak of Shadows instead).
