Factual error: At the dance in 1947, a US flag with 50 stars is visible.
Invincible - S1-E5
Factual error: Henry Deacon says people only use 10% of their brain at any one time. That's complete garbage - at times we may use quite a small part of our brains, other times the whole brain lights up with activity. The "10%" myth has absolutely no basis in fact - no-one even seems to know where this figure came from! Given the intelligence of Eureka's residents, Henry (and indeed others in the room) would know this.
Factual error: Zane used ULF (Ultra Low Frequency) to communicate with Henry and notes he can "only send numbers." This is a reference to extremely low bandwidth of maximum 300 Hz transmission. However, later Henry magically creates an upgrade that allows voice communication - not possible with ULF. Also, no way Sheriff's old radio would pick up ULF band communications in the first place.
Chosen answer: He's still around, we've just not seen him lately, as scenes with Blake have been mainly at work, where Kevin wouldn't be.
Tailkinker ★