Mulligans
Mulligan: Just go for all your Spells and Sea Giant, you can keep Stubborn Gastropod too, but only if you already have 2 other spells/Sea Giant in your hand.
The deck can get cheaper if you just just put good 8 drops such as Force-Tank MAX, Eldritch Horror, even Doomcaller, anything goes, it just needs to be a big 8 drop.
Pretty easy win.