This is far too strong. Even if you exile it, you can still get a huge burst of mana without even having to pay life.

A couple of points that apply across your set:

-You don't need to hit enter twice when separating abilities. Makes the cards look a little awkward.

-There's a couple of cards like these that have these absurd drawbacks and utterly bonkers abilities. All of these cards are not fun for either the player or the person on the receiving end - basically, it turns the game to sudden death mode, or is utterly useless sitting in your hand if your opponent went with an opener of Goblin Guide -> Lightning Bolt, Goblin Guide.

I also might take a look at Magic design as a whole and try to understand why they make the decisions they do - i.e. limiting the power of tap abilities, understanding the power of fast mana, knowing when "win more" cards get too out of hand.

Don't take this the wrong way - you have some nice designs here and there, and some of them are interesting, but it's a little difficult to sort through all of them with all of the bonkers conditions and payoffs you're giving them. A lot of them would play a lot better if they were toned down.

Balancing large effects with enormous unrelated drawbacks is terrible design anyway - and especially something to avoid on lands.

I know. I feel like shit

There's no need to feel that way. It takes a lot of time to be "good" at making cards. Nobody starts off unilaterally skilled at all aspects of design.