Black Vulcan, Apache Chief, Samurai and El Dorado are all owned by Hanna-Barbera, so I'm pretty sure they're off limits, unless some sort of special deal could be worked out.
The Wonder Twins, however, are owned by DC, and Rima's in the public domain, so those characters should be possible.
DC and Hanna Barbera are both subsidiaries of Warner Bros...
And it's already been established at San Diego last year that Mattel now has the right to use those characters. The only rights issues are still with Charleton characters. All WB/HB/DC characters are clear.
Can you point to a specific source for this?
The hanna barberra characters from the Superfriends was a gray area I was never sure we heard an answer on.
The 2007 Comic Con Mattel DC pannel, there was a representative from Warner Bros, she was about 40-ish (woman) she responded to someone's question regarding this specific issue. She confirmed that the HB superfriends characters are in fact available.
One can assume that even the name SuperFriends was HB trade marked... but that's been included in the new license as the line of preschool figures are called SuperFriends.
Hope that helps. I wish I could remember the name, but it was very clear that they had the rights to Black Vulcan, Apache Cheif, the WonderTwins etc... weather or not theyd actually MAKE them... is a different story. But they are available.