Weedle130

If the RXyz Summoned by it has its base form as an Xyz Material, it gains another effect.

The R is for “Reborn”

Normal Spell Effect:Target 1 face-up Xyz Monster you control; Special Summon from your Extra Deck, 1 “RXyz” or “Number R” monster with the same Type as that monster you control, but 1 Rank higher, by using it as the Xyz Material. (This Special Summon is treated as an Xyz Summon. Transfer its Xyz Materials to the Summoned monster.) When the Xyz Monster Special Summoned by this effect is destroyed while this card is in your GY, return it to your Extra Deck.