Ambush Commander VS Oblivion stone

[Offler]

Opponent has Ambush commander on battlefield, i had Oblivion stone...

The attempt to use the stone ended, when we realized that we didnt know if it will or will not destroy all lands of my opponent.

[Julian23]

Oblivion Stone says "non-lands". Ambush Commander says "are still lands". You go figure :-).

[Offler]

Thats exactly the point where we ended up the game, because we were not sure :D

Commonly there are some things in play which as i think do not follow the rules exactly as it is normal.

Some example:
A player has manland in play. Other player will cast Doom blade on it. Usually player who owns the manland (currently being a creature which is still land) will throw the land to the grave. Only one skilled legacy player told me that Doom Blade will be countered.

At this point i became confused.

Since such play is common here there is no point to ask on local forum here.

Therefore i can only guess that it will not affect any permanents which are currently lands, even if they have another permanent type.

[luma]

Nonland permanent means "a permanent that is not a land". Lands animated by Ambush Commander are still lands, therefore they aren't "nonland permanents".

Doom Blade will work on an animated manland, because the land is also a creature and that's all Doom Blade cares about. If the manland weren't a legal target, you couldn't even cast Doom Blade on it. The "Doom Blade gets countered" makes no sense.

[Julian23]

Doom Blade will surely destroy an animated manland unless it is black, indestructible or has e.g. shroud.

To clear things up: Oblivion Stone won't destroy animated manlands.

[Offler]

Now its clear. It was not the doom blade, but Maelstrom pulse. Other commonly played spells here are planar cleansing and [cards]child of alara[cards].

According to your advice none of those (oblivion stone including) will affect manlands.

Thanx.

[Julian23]

Unless the manland says something about "...is no longer a land". However, I can't think of one that does so.