Zanz, flooding buff is not the solution.
First, flooding with only 5 creatures on the field ruins all the creativity of mass creature decks such as pharaoh, firefly, mitosis, fractaling, graveyard combo, emphatic bond combo.
Plus, it is not only ruining, but also makes a gigantic additional shield.. So, it is like second shield.. works better than gravity shield which only block enemy creature's attack, but also kill enemy creatures, like pandemonium or fire storm effect..
Then, it is very super duper cheap..
Then, it is only works for enemy creature (if your deck was water). Water creatures in players field not affected.. Ridiculous effects..
Then, make it combo with Shard of Patience, make it more more dangerous.. (but flooding can work alone which is ridiculous also).
Zanz.. Think about it... It make more players tend to build only a single creature in their field to win, such as:
deathstalker+unstoppable+adrealine+Quint Essence..
Which is ridiculous deck i have found in many pvp, and make me sick..
Think about it zanz.
Make flooding work for 5 creature will make your elements the game ruins.