Some G1 playsets have been re-issued. You can see the difference among others in the variation of colours and sometimes the playset got another name. Just like the G1 ponies there are also both USA and International playsets.
G2: 1997-2003
Some of the G2 playsets have been displayed in a leaflet, but were probably never sold anywhere. There is also a playset which is almost identical to a G1 playset.
G3: 2003-2011
The G3 playsets are very different from the G1 and G2 playsets, because the ponies can activate lots of fun things with their hoof hearts.
G4: 2011-present
G4 playsets are not only suitable for the My Little Ponies, but also for their little animal friends.
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