Mashup of Steam Vents and Shinen of Stars' Light

Hm. A minor effect on a discard is a tweak we've not had on dual lands before. I guess the downsides are (i) it's too easy for it to feel like a spell, not a land and (ii) it has to be useful in the late game when you want to discard lands.

So this may not be printable, but I was interested in the idea. Hopefully the effect is small enough you'll usually play it for the land, and accept the channel effect as a small bonus, rather than treating it as a spell which landcycles.

Yes, I think you've achieved that quite nicely. I like it.

Could perhaps be uncommon, since Izzet Guildgate has brought the base effect to common, and this is unlikely to be great in tournaments since it can't ETB untapped.