Land becomes a 3/3 that can block or be tapped for mana on what's left of that turn cycle, and then can be pumped to a 6/6 after combat or you can make a second 3/3 land...
This card hurts my brain to think about what it does, and having a maybe tapped 3/3 after combat doesn't seem great but the flood protection of all lands being at least a potential 3/3 in the late game feels very good.