So, never buy packs from the store - you'll get the twice the value on average even if you do terribly in a Ranked draft
In a deck with an abundance of low-costed creatures, as red often has, it isn't too hard to find one goblin token or construct creature to throw in the bin for the mana
To help in your endeavor to lay down massive damage, you could use Full Metal Lab from the Scarlet & VioletTemporal Forces expansion, which will soften the blow of incoming attacks (handy considering Doublades fairly low HP)
The Horror House- GX attack doesnt cause any damage, but it will certainly disrupt your opponents strategy by preventing them from playing any cards from their hand during their next turn
Deadbloom Predator also pairs well with Dazzling Aurora, allowing you to cheat it into play from your Gear and instantly swing a battlefield in your favor
Gyarados ex is a Water-type TCGP card that offers the player expensive and unrewarding attacks, making it the worst ex card in the mobile game