This is extremely difficult to limit to only three here, but im going to do my best and add small explanations as to why:
pretty sure this needs no explaining here if youve read other posts by me, but this card really pulled on every heartstring i had in re entering collecting. The art is amazing, its happy as can be, and never fails to put a smile on my face.
Another favorite from re entering. This one here stems from my love for Dedenne and how much it grew on me, showing me that theres even newer mons i can love and enjoy aside from the gen 2 gang that i always show affection for. It began when I rescued a hamster alongside my gf and after having him, nursing him back to health and giving him an amazing life, he sadly passed away a few months back. However cards like this helped me so much to remember all the great times with the little fella, and forever theyll keep his memory alive with me so the sentimental attachment is definitely real. 
Now this one was a coin flip. On that same theme of new and fresh cards, im finding that in my later years as an adult, while the childhood memories of pokemon were great, the ones im making now are even better. As for Typhlosion most already know its my top tier fav mon, and typically Dark Typhlosion is what would take this spot here. However I have to say that this art pushes every single button for me and i adore it. It has that cartoony look i enjoy, a great attacking pose, and a background thats just killer compared to 99 percent of other typhlosion cards. its a simple rare from Lost Thunder, but even in more lesser rare cards these days the arts were blessed with are just killer. So ill leave this as my rotating number 3.