I'm not a big fan of the Ambush! Series however I think this a good card.
Why? (to both statements) I would like your input so I can improve.
Because for it to have any use you would have to fractal it THEN use it's ability to get them all into ambush position. It takes a whole turn to move it into ambush position which by then your opponent could have destroyed all your creatures with Duo RoF or Triple Thunderstorm.
Also another weakness to all your cards:
Alligator: Requires 3 elements to make a good Ambush (Aether + Water + Life)
Wyrm: Requires 2 elements to make a good ambush (Aether + Earth) and halving all their attack.
Dimensional Striker: Un-Fractalable.
Those are just a few examples.
Anyway my point is for it to be effective you need to wait a whole turn to use abilities + you need Fractal.
The idea is still brilliant however, but needs improving.
I like this because when submerged it cannot be targeted and it's damage stays the same (unlike burrow) and it strengthens the Water + Life combo.