Just a weird card concept inspired by Jack V talking about tapping islands. Probably not common.
Flood could either be left at flood or extended to "flood target land." That's going to have to go in the reminder text anyway, so it's an aesthetic choice.
Also, this creature is meant to illustrate that I think creatures that flood should do something with the flooded lands.

After some thought, I prefer "When ~ ETBs, flood target land." That way, maybe in the second set, we can develop the mechanic and have some bizarre creature that floods other creatures or something.
Also, I don't think this ability would work quite like I want it to, but I don't know how to fix that.

I think "flood target land" sounds most natural, and is probably best for the rules as well.

I've added reminder text via the set's mechanic support. We can tweak the reminder text as we want.

This is a delightful design. It functions like a Sylvok Explorer as well as enabling flood-matters.

I really do like the ability, and I think the way I implemented it makes it much more blue than would normally be. However, right now, can't you target a tapped land? And is that okay?

Yes, you can. It seems fine to me. Streambed Aquitects didn't restrict itself to untapped lands.

Or are you thinking this should have the flavour that we're drawing mana from that land, so it should be untapped? That'll be really hard to have as a targeting restriction, because the opponent can always tap the land in response.

I also like the way that this could allow you to cast a card if you have two Plains and an Island, but have a flood counter on one of those two Plains.

That was the flavor, but I think it just works more cleanly without the restriction.

I like the idea, but it's too cheap for common. I know many players weren't around when Rishadan Port was wrecking tournaments, but... it wasn't fun. Tapping your opponent's lands used to happen all the time in the early days of Magic (I've been seeing a lot of it in Mashup: The Gathering) but doesn't really happen too often nowadays for the same reason that land destruction is rarely a viable strategy. I do think we have room for cards that tap the opponent's lands, but they shouldn't be this early in the game (I mean, this low a casting cost), and they probably shouldn't be tournament worthy.

Owch. You're right, this is a Rishadan Port, and I completely missed it. Admittedly this is a heck of a lot easier to kill than the Port was, but still.

Perhaps this concept could work without tapping that land. That does make it feel a little more green/less blue, but it's still specific to Islands.

But it's not a big problem if this specific idea has to die. The potential of flooding to be fun and interesting seems to have been demonstrated.

Yeah, I like this design, but I thought of mana-denial as a one-off, not a repeatable to avoid a lockdown; I agree repeatable tap-down shouldn't be common, and may just wnat to be jetissoned.

I have kind of a soft spot for this card now, but I guess if it has to go, it has to go. I didn't really intend for it to be common, I just didn't change the rarity. It could even be rare, if needed- it's like blue's Birds of Paradise.

A 1 drop that floods a land when it ETBs would be fine. The other ability is too far out of Blue's colour pie to go on a creature.

If you want a blue Sylvok Explorer type creature why not just have it tap (with whatever costs/restrictions you like) to add one mana of any colour a flooded land could produce.

Flooded Land seems to me to work well as a reference to 'land with one or more flood counters on it'.

What about a common that floods a land when it ETBs and un-floods the/a land when it leaves the battlefield.
has the removal of flood counters been addressed yet?

No, because flood counters are just there as a reminder. Currently, the flood mechanic permanently makes the land an island, regardless of whether or not the counter stays.
Blue has limited mana generation. Though it usually pertains to artifacts, I thought that perhaps this cared enough about islands for it to stretch.

OK, I haven't kept up on whats going on here as well as I should so please forgive my ignorance.