The Invincible comics are full of Easter Eggs that are still being discovered years later, though artist Ryan Ottley revealed a few in a Reddit AMA.
Yes, Invincibleand Spider-Man have canonically met in a crossover ... In Invincible #33 by Robert Kirkman and Ryan Ottley, Levy has invaded Mark's home, intent on seeking revenge.
The original Invincible comic by Robert Kirkman (The Walking Dead), Cory Walker and Ryan Ottley did a near-perfect tightrope walk between satirizing superhero tropes, playing in them earnestly.
Superstars Robert Kirkman and Ryan Ottley present the most demanded Invincible story of all time, revealing the secret story of Battle Beast that's perfect for any long-time fan (no spoilers!) ...