Sea Colony, the ninth Sea <l:6,66>Advance<e>, opens the deep ocean to colonization. Supported by the <l:1,7>Sea Engineer<e> and defended by <l:1,3>MINe-Fields<e>, these new <l:6,105>Sea Colonies<e> create a Civilization beneath the waves. Finally, Sea Colony Advances allow for the construction of <l:8,6>undersea mines<e>.
