Treasure Hunt Mobile RPG Event Illustration

[Game Campaign] - Game Title: Treasure Hunt! - Game Overview/Features: Find treasures on a great adventure island! - Genre/Subtext: RPG Adventure Action! [Quality, Production, Composition] - Style: Illustration for event announcements for Japanese mobile RPGs or casual games. A colorful and joyful fantasy world. - Subject: Adorable chibi characters (deformed heroes or mascots) opening a treasure chest with smiles. Golden light and magical particles are overflowing dazzlingly from the chest. - Background: Blue sky, white clouds, and islands or forests in a lush fantasy world. - Typography (for GPT-image / Nano Banana Pro): A fantasy-style decorative logotype of Treasure Hunt! is designed in the center or top of the screen, with Find treasures on a great adventure island! and RPG Adventure Action! added in an easy-to-read layout. - Color/Lighting: Bright, high-saturation fantasy colors, magical gloss, and soft shadow depiction. [Strict Layout and Output Constraints (Required)] - Output the finished design itself, filling the entire screen. Backgrounds and scene descriptions (walls, spaces, shadows, etc.) within the design may follow the instructions in the main text. - Prohibitions: Photos of the finished poster in a frame, photos pinned to a wall, mockup photos placed on a desk or paper, perspective distortion of paper edges, or drop shadows. - Output the finished flat 2D design itself, filling the entire canvas. Scene elements inside the design (walls, rooms, shadows) described above are allowed. Absolutely NO photo-of-a-poster mockups: no picture frames, no poster-on-wall or poster-on-desk shots, no perspective warp or drop shadow around the artwork's edges. - Aspect Ratio: --ar 16:9