You could just use Domain to summon Kentregina then use her effect to get to Stealthbegia
Deck Legendary Secret Rare 20th 20th Secret Rare Ultimate Rare Rarity Collection Battle of Chaos Dimension Riryoku Dimension Riryoku Thank you so much for visiting [Medusas Serpent Mansion]
The difference is that for the video games this is an outrageous con, a way to charge you twice for one game, but in the card game it's actually pretty advantageous for the consumer
Gradius's Gaiden Counter Trap Card Lore: When the effect of a monster with more ATK than the ATK of a Level 4 LIGHT Machine monster you control is activated: Negate that activation, and if you do, that monster has its effects negated if it is on the field, and if it does, its ATK becomes 800
Contagion Clasp and Contagion Engine are the best ways to achieve that, but Bloom Hulk and Pollenbright Druid are on-theme proliferators
This version, which uses the Ravnica Cityscape frame that also works so well with the Multiverse Legends Juri, Master of the Revue has some sweet pen and ink art by Isis that dovetails with the frame and looks like Niv is both folding the city within his wings and scorching it, just a bit