However, you must still follow any other timing restrictions, such as "Cast [this spell] only during combat." (8/23/2016) You can't pay any alternative costs the card has
I imagine the play pattern will be to cast Seek Thrills first from the command zone, and then once Beluna ends up back in the command zone, youre already at the five mana youd need to just cast Beluna Grandsquall
Whenever one or more Vehicles you control attack, create a 1/1 colorless Pilot creature token with This creature crews Vehicles as though its power were 2 greater..Crew 2 (Tap any number of creatures you control with total power 2 or more: This Vehicle becomes an artifact creature until end of turn.)
These instructions will apply to any version of the game you are playing, though the screen shots are captured from the PC version
The worst part: even though Dual Casting is a tap ability, you can usually put the aura on a creature which was already in play so assuming the spell you want to copy is an instant, you can go from innocuous boardstate to comboing off in the same turn for just four or five mana
Graded Population Report: Wigglytuff ex #40 Visualize the distrbution of grades in the chart