Flood Plain

Flood Plain enters tapped.
{T}, Sacrifice Flood Plain: Search your library for a Plains or Island card, put it onto the battlefield, then shuffle.

Port Town

As Port Town enters, you may reveal a Plains or Island card from your hand. If you don't, Port Town enters tapped.
{T}: Add {W} or {U}.

({T}: Add {W} or {U}.)
Glacial Floodplain enters tapped.

{T}, Pay 1 life, Sacrifice Flooded Strand: Search your library for a Plains or Island card, put it onto the battlefield, then shuffle.

({T}: Add {W} or {U}.)
Idyllic Beachfront enters tapped.

{T}: Add {C}.
{W/U}, {T}: Add {W}{W}, {W}{U}, or {U}{U}.

({T}: Add {W} or {U}.)
As Hallowed Fountain enters, you may pay 2 life. If you don't, it enters tapped.

Azorius Chancery enters tapped.
When Azorius Chancery enters, return a land you control to its owner's hand.
{T}: Add {W}{U}.