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Hi all. I've seen that in my custom version creatures with morph activate Rules Engine but, when I do, nothing happens. probably my version is missing the card used for Morph ability. May you tell me the slot used in Constructed Version, please? Thank you.

Around 1990 or so on.

Is it the "data card"? ID 909
Also... why aren't you using slot 1999? it is still good! I've used it in my custom version and it is just going great Also, in constructed, there are a bunch of empty slots... aren't you using them because they may be related to some invisibile effect?

No, is called "Face-down creature".
All the usable slots in the costructed version are filled. The remained ones are used by some effects of the original game and are not available.

Ah, thank you! ) Anyway, I'm 100% sure that slot 1999 can be used