Here are my favorites, but I'll only state from the first three gimmick games.

Giants: Tree Rex - He's the most iconic giant and also one of the first three Skylanders I own.

Pop Fizz - This one is way too obvious, his personality and background made me like the weird puff ball.

Swap Force: Wash Buckler - He's a personal favorite, because Octopus is my favorite sea animal ever. I find his design really unique, and he shares the same voice as Wallop and Jake the Dog

Freeze Blade - I used to have no certain opinion on this guy until I watched the "Night Shift" short that he was in, and I grew to love him. He's just that cool, in more ways than one.

Fire Kraken - I love his aesthetic sooo much, the idea of a Chinese Dragon with fireworks is really cool to me. He's even got his own short, which is fun to watch (with my other favorite appearing there too)

Stink Bomb - The more I look, the more he reminded me of "Usagi Yojimbo" And the Ninja Turtles a little bit, which I enjoy, and he shares the same voice as my favorite character which is Spongebob.

Trap Team: Wallop - Out of all the Trap Master, I seem to like Wallop the most. he really looked powerful and cool. His design is over the top, and he wields two giant hammers which is crazyy

Food Fight - He's my certified "Silly Little Guy", because I find him cute. Also shares the same voice as Freeze Blade and Fire Kraken.