OFB-9

Actually, the point was about 4 Dimension Door for the player catching up, not for both, but it's better to discuss that in another thread

and how do you determine who is "catching up"? How many loopholes will appear in the rules, and players will be in unequal conditions; for example, you are catching up to him, and with 4 Dimension Door, you might even manage to collect 2 Dragon Utopia on the way, for instance, while your opponent cannot.