10) Suddenly started referring to his daddy's comics as "our" comics.

 9) If he gets hot chocolate in a Spider-Man mug, it's "Spider-Man hot chocolate". If he gets hot chocolate in a Captain America mug, it's "Captain America hot chocolate"... etc. etc.

 8) We play the alter ego game; who is Batman? Who is Robin? When asked who is Firestorm, he answered "Kurt" (manager at the North store).

 7) Often referred to his older cousin Justin, Justin's twin brother and Justin's friends as "the Justin League".

 6) "but my baby brother likes getting hit in the face with my giant noise-making Hulk gloves..."

 5) Announced at dinner that General Zod attacked his school earlier today.

 4) When asked what he keeps in his utility belt: Batarangs, tracking devices, smoker bombs, gas grenades, & chicken nuggets.

 3) When I asked him why he left his playdoh all over the kitchen table: "Well, you see, the Legion of Doom came and took the Justice Weague and I made a new one from Playdoh to save them... Batman Blue (blue), Batman White (white), Batman Red (purple), Firestorm (orange) & 2 robots (mixed colors)..."

 2) When he heard his mommy ask his daddy if we needed anything special in the family budget for next month, he looked up from his ice cream and replied, "a Hawkman guy to go with my Green Lantern guy".

and the number one...

 1) Once, when told by his mommy to go upstairs and get ready for bed, he reached into his underwear waistband, pulled out a Lego and yelled "smoke grenade", tossing it at my wife. She told him again, in her stern voice, to get ready for bed. He yells, "no effect", pulls out 2 Legos, tosses them and runs. She looks at me with the mean scowl and says without saying, "see what you are teaching him?" To which I shrugged, "Ugh. I told him smoke grenades would not work and to use gas pellets instead."