This old deck has seen a semi-recent renewal with the printing at common of a few cards thanks to supplementary product.
It has never been at the top but it is still a very powerful and efficient deck. The printing of Hooting Mandrills helps it a lot, giving the deck a critical mass of cheap, big beaters.
This is a tempo deck. It can play longer games but it prefers the games where it will have an early threat and then counter and bounce a bunch of thing before delivering the final blow. While the casting cost of many of its cards is rather high, this deck operates on a very low curve of 2 to 4 mana. Playing all of your lands is not always necessary since they can be discarded late-game to careful study, wild mongrel and merfolk looter.
Speaking of careful study, it's not a card that should be cast simply because you can. Turn 1 it can be really strong if your hand includes a rootwalla. Turn 4, it can cast an arrogant wurm. Later in the game, it can be used in combination with 2 lands in hand to draw 2 fresh cards. This is easier to accomplish thanks to cards like Daze and Gush, that will bring back lands to hand.
Basking Rootwalla can be tempting to cast turn 1, but if your hand includes a merfolk looter or a gathan raiders, it can often be better to keep the rootwalla in hand in order to discard it for a free card later on.
Deep Analysis is very good discard fodder. Casting it for 4 mana is a bit unrealistic, so don't hesitate to discard it and to draw 2 for only 2 mana.
Don't forget that most of your discard outlets function at instant speed. It can make it very hard for control decks to control the game when you're holding an instant speed 4/4 (Arrogant Wurm) and counterspells.
Sideboard Plans
vs delver-fiend
+3 Hydroblast+1 Waterfront Bouncer+2 Exclude+2 Piracy Charm
-2 Deep Analysis-2 Careful Study-2 Gathan Raiders-2 merfolk looter
vs Kitty +2 Exclude+2 Dispel
-1 Waterfront Bouncer-3 Vapor Snag
vs MBC
+2 Exclude +2 Dispel
-3 Vapor Snag-1 Waterfront Bouncer
vs delver
+2 Piracy Charm+4 Scattershot Archer+2 Dispel
-3 Vapor Snag-2 Merfolk Looter-1 Waterfront Bouncer-2 Gathan Raiders
vs G tron
+2 Exclude+1 Waterfront Bouncer
-2 Daze-1 Circular Logic
vs burn
+3 Hydroblast+2 Piracy Charm+2 Dispel
-3 Vapor Snag-1 Waterfront Bouncer-2 Deep Analysis-1 careful study
vs teachings variations
+2 Piracy Charm
+3 Dispel
-1 Waterfront Bouncer
-3 Vapor Snag-1 Aquamoeba
