MEGA Pokémon Build & Show Squirtle Construction Set, Building Toys for Kids

Hi, I'm going to buy it, but is there a possibility to have it shipped sooner? before December 25th???

Are these really truly compatible with Legos? My son has thousands of Legos and gets very frustrated if an “off” set doesn’t fit with his other bricks

Do you actually put together the item? Or does it come pre-built?

Is there a venusaur?