However, you can always use cards with cycling like Lrien Revealed at the end of your opponents turn to fetch a card, and, more importantly, exile the card on top of your library to play it on your turn with no restriction
The key takeaway here is: If an MTG card has several types, everything that affects one of its types affects the whole card
As for what it does, thats hard to tell because it literally doesnt tell you
It's an incredibly useful card, and one which has attracted a wide variety of artwork variations, thanks to its inclusion in multiple sets
All those Magic players, drawing their cards, slinging their spells
However, this Red or Blue Land card (an Island Mountain, being both types at the same time despite only being able to provide one type of mana each turn) is still ludicrously expensive even if you opt for the lowest cost version on offer via Cardmarket