Starting up, you're going to always want to go first, so you can counter their every move and play on their turn.
You're almost ALWAYS going to want to bring Sera out to set up your combos, normal summon a Traptrix and link immediately.
If you don't have a Traptrix, thats why theres two Magical Mallet in the deck, also in case you draw into Double Or Nothing! you can reshuffle it for the Utopia combo later.
If you drew into Shade Brigandine first or second turn, then when you bring out Sera, activate after to activate Sera's effect to bring a Traptrix monster.
Myrmeleo's effect is MANDATORY, even if your opponent doesn't have a spell or trap to destroy, the effect still triggers.
Which triggers Sera to set a Trap Hole.
Another big combo, is while you have Sera on your field, and a trap in the same column, if you get to activate the trap (Which activates Sera) you can Special summon Myrmeleo RIGHT BENEATH Sera in the same column.
Myrmeleo's effect triggers popping your opponents spell or trap, or triggers anyway. This triggers Sera and you set a trap RIGHT BENEATH Myrmeleo in the same column.
Now that you have three cards in the same column, Iron Dragon Tiamaton gets special summoned to another main monster zone, destroying all other cards in that column, neither player can use zones IN that column either.
Keep in mind that either player can have more than one Extra Monster Zone, if you have Sera out, they cant Link summon if Tiamaton is blocking the other zone.
Now they have to Normal or Special summon monsters the traditional way to get rid of Sera, or use a spell.
If you brought Rafflesia out, your opponent cant target Sera with effects anyways.
PLUS you have the Floodgate Traphole set by Sera in addition to other Traps you have, limiting them tremendously.
If going first and can Xyz, then I recommend Raflessia,Tornado Dragon, Redoer, or Allomerus, but only if your opponent is using a deck that has many level 4 monsters.
If going Second then Borrelsword or the Utopia combo if set up right. Pentestag can allow either to pierce so keep that in mind.
Sera activates to ANY normal trap, even your opponents.
Sera is ALSO unaffected by traps in general, meaning you can use your own on her to get her effect to trigger.
Dionaea can target another Dionaea in the grave, which will activate her special summon effect.
Dionaea special summon effect is to set a Trap Hole from grave but banish it during your next turn if still on field, Mantis has a Quick effect however, to bounce one of your Spells/Traps to hand and set another. Getting rid of the bad effect of Dionaea.
Good luck, those are the main strategies I use while shutting down my opponent!