Ink-Treader - This works really well as a combination of burn and graveyard hate, and I think that it'd be fun to play with as cool sideboard tech for a Rakdos aggro deck.
Ryder - This is an interesting retooling of
Chandra's Ignition, but it doesn't really feel that innovative.
Icarii - I like the card and that it tries to give you a bonus if you have to play it sub-optimally. Cool idea!
spacemonaut - This seems about balanced for a big X spell (maybe on the strong side), and although I don't normally like unbalanced mana costs I think it works here to tie this together as a mainly red card. I do think it would have worked better as mono-red, though.
bravelion83 - I think that having all of these abilities tied together is a little too powerful, as you get to kill two things and deal a lot damage to a player. Furthermore, this spell doesn't actually work, as there needs to be a target with flying for you to cast the spell whether you pay
G or not, which seems like an error - use "up to one" for all of the targets.
Koopa - While this is a cool idea, it's also pretty weak, as if you want to have this deal more damage than a Shock, you have to either sacrifice a planeswalker or have a great deal of set-up. It's also win-more in that if you have enough planeswalkers to kill an opponent off of this spell, you've already won.