These are super nerdy and grognady cards to talk about.
Into the roil is interesting because in my experience it really excells as "control bounce" rather than as a tempo bounce, though you can run it in tempo. Bounce is a really strong effect, but one that the attrition focused "control" blue jund style effects get somewhat disadvantaged for running, because trading a card for time isn't really in focus with what they are trying to do. With its higher mana cost, and replacement effect, I've always found into the roil to slot much better into attrition decks, to the point where it eventually moves down tempo blue's pick order, and up attrition blue's pick order. This is the same draw as repeal, which is also somewhat mana intensive, and replaces itself. Its also
really important that both of those spells can hit any pernament, which is a big part why you would even consider them in a control shell in the first place, and the cantrip just seals the deal.
The blue tempo decks
can run it, but they tend to be super focused on efficiently using their mana each turn, and holding 2 mana up is a real cost, for which they can be punished for. Something like
vapor snag (or spell pierce/force spike) slots much better into those decks, I find.
I actually think snap is really undervalued in the cube card hierarchy, though I can understand why. Even though ultimately being a 0 mana spell is big game, and enables some back breaking plays in conjunction with counter disruption, requiring an initial 2 mana to be held up looks really rough when you are pushing mana efficiency every turn, especially if your soft disruption is more
spell pierce than
mana leak. I still think it plays really well though, and a good player can really engineer blow-outs, and surprise chain disruption, in ways you just can't do with other bounce spells. The other big issue with it is that there is nothing really exciting to do with it in a control shell (unless your format runs bounces, where its sicks), and it also can't hit any pernament, which is so bad, and makes it more narrow though still functional.
Obviously, this is a pick order/game play observation, so I'm ready for contrasting experiences.
When I first saw perilous voyage, the first thing that went through my head was
magma jet, and I suspect it will play better in a tempo shell than into the roil, but worse in a control shell, though I'm still not super excited about the card. Not being able to hit your own creatures at all is actually a pretty big deal--play wise--in a blue tempo build, and is a relevent niche play to be able to make, though this obviously depends on how good at mtg your players are. This and costing 2 mana is actually a pretty big disadvantage when compared with vapor snag, but the scry is really sweet for those decks. I feel like it might dilute too much from those decks' plan for winning the game, but casual cube groups will probably care too little, and enjoy the scry more.
Being able to hit any pernament means it passes step 1 for an attrition build, but scry 2 is much worse for those decks than draw a card, and the cheaper mana cost isn't something they really care too much about. Though again, doubt that a casual cube group is really going to notice/care about the difference.
Probably the biggest problem with the card is that there are so many excellent alternatives, that it may be pushed out a slot, despite being servicable. This does seem to be the type of stapled on effect that players like/appreciate, so I wouldn't be too quick to turn it down.
