Level 4 ATK and DEF conventions

The "Rule of 2000" is a general rule that previously applied to Level 4 or lower Monster Cards, until the release of Gene-Warped Warwolf in Strike of Neos. The "Rule of 2000" stated that once Monster Cards got to 1900 ATK, to go further, to 2000 and beyond, Special Conditions had to apply to the monster to limit the card.

However, DEF does not have a "Rule of 2000", instead, it has a "Rule of 3000"; 2000 DEF Monster Cards are plentiful, and many Level 4 or lower Monster Cards have DEF equal to or higher than 2000. However, most monsters with 4 stars and 2300 or more DEF are usually limited in some way (such as Destiny Hero - Defender). 2200 DEF monsters were rare, but now are quite plentiful, as are 2100 DEF monsters. This can basically be explained by the Defense rule of 2000.