Use "Photon Veil" to return 3 LIGHT monsters to your Deck and add 3 "Thunder Sea Horses" to your hand. Then you can discard a "Sea Horse" instead of Special Summoning during a turn to get 2 "hunder" monsters during any turn. This will speed up the Deck thinning and allow you to search out the cards that you need and when you need them. Remember that this card's effect can only be used once per turn.
Use this card in triplicate. Use the first to search out the remaining two from your Deck. Hold them in your hand until you know you will not Special Summon for a turn and this becomes a great way to search out almost any monster in these Decks.
Xyz Summoning a Rank 4 monster can become quite easy with this method; however, you will have to wait until the next turn to do so. "Mahunder" and "Pahunder" can also be used.
Use the effect of "Thunder Sea Horse" to search two "Sishunder" from the Deck. Then Normal Summon "Sishunder" and banish "Sea Horse" from the Graveyard. During the End Phase "Sea Horse" will return to your hand, so you will be ready to use its effect again next turn, and you will be able to Summon once more by the remaining "Sishunder".