foil miraidon pokemon card - ex 253/198 - Scarlet & Violet - Secret Rare Dragon / 110 / Basic Attack 1 Miraidon - SV05: Temporal Forces

One thing to note is they regularly have sales on high rarity cards, so it's worth checking out their twitter before you head in to see if you can snag a deal

Multicolor Matters is already a somewhat supported theme, and it can work well within this archetype

Theme Card Thryx, the Sudden Storm Voracious Greatshark Delightful Discovery Brineborn Cutthroat Capture Sphere Naiad of Hidden Coves Opt Pestermite Spectral Sailor Starlit Mantle Stinging Lionfish Undersea Invader Thriving Isle 7 Island 0017_MTGJ25_Theme: Surprise

He has a power of 2 and Life of 3 as well as the abilities Lifelink which lets you heal for all damage he deals, and Throw Wide the Gates