Of the cards i actually own... my thoughts on the ones that don't get the attention they deserve are

Ulu Watu- Shayna She is a monster 4 star card. Base stats of 6/5 But if hit both ability and bonus, she is a monsterous 11/5
but she is overshadowed by Buck, but i like her over Buck b/c she is less succeptable to soa or sob.

Also Warren, yes, Warren a measly 2* card that you can get in a starter deck But if you know when to play him he can kill his
opposition and throw them into the wind. But Bree and Taigo overshadow him just too much, but i still got love for him.

Nightmare- Erzsebet: Where is the love for her? 6/3 (low damage i know) but she is the 3 star Eadh with 1 lower minimum
of 4 instead of 5 on the power reduction, I love using her in a Azgroth and Eadh combo, tends to tic off your opposition.

Roots: Amanie. Personally she is one of my favorite 4 star cards in Roots. But she is too suseptable to SOA. But still
if she gets her ability unapposed? She is a 7/7 4 star card (virtually) or even 7/9 if you fury her..4 stars is huge
for her card, but still i would like to see her more often.

Jungo: Last but not least, has to Be Boohma. i know his stats are 4/5. but in mono-Jungo, he can rule the jungle.
support=atk plus 5. I have called a bluff with him without pilling and landed 5 damage, because with his ability he can
land a monsterous 24 attack without pilling whatsoever.

Zeke, 'nuff said.

I think Boris is pretty underrated as a Freak. Most people pick the bigger Olga and Noel and Akendram. But he is sorta like a prototype of Oshitsune, just no SOB so he has the All Star, GHEIST, Root, and attack Manip weakness. But he works wonders when paired with Ambre (like most Power Reducers)

All Stars: Liu. No one uses her. Ever. Except me, and people see 5 power and write her off, yet the PR and SoB usually allow me to get a 7 or even 9 hit on them, with very little pills. Way better than people think she will be.
Bangers: Massiv. I know, he annoys a lot of people. But the 4/4 stats at first glance cause people to dismiss him, and if you play him against a non-SoB you can win almost every time.
Fang Pi Clang: Sayura. She is SO cheap for what she can do. If you play her right she can do 9 damage, which you CAN if you bluff with a more intimidating card to begin with.
Freaks: Titus. Again with the 4/4 stats, but if you's not versus a SoA, it's an awesome card. Poison is usually done by the time you use him in your deck, but he is awesome for using after a bluff.
GHEIST: Platinum. He weakens so many cards, and is unbelievably cheap. Yeah, he doesn't have huge damage or anything, but for stopping 'powerful' cards in their tracks, he works wonders.
Jungo: Jalil. I love Jalil. He might be one of my top 5 cards in the game. He has 2 life bonus, -2 life ability, and 3 damage!! With fury it can be a 9 life difference!! Amazing, even if there is a SoA or a SoB.
Junkz: Dreen. I see her from time to time, but when I have used her, I won almost every time. People do not have her in their Junkz decks often enough! And she is SO cheap, and I don't get why.

La Junta: Chiro. I started playing UR with La Junta and saved until I got to level 20 or something before I branched out, and Chiro is the card that dragged me through it all. I rarely see it in use anymore either, which surprises me.
Montana: Milovan. He used to be used a lot but has all but disappeared, due to way more intimidating Montana cards. I loved him because he cut an opponent's life in half with the LR.
Nightmare: Nistarok. It's 5* and most people will choose Ghumbo over him and not take another 5*, but his DR and high power make him hard to read.
Piranas: Kristin. I almost never lose with Kristin, either due to her bluffing to force pill play, or decent stats. I usually open strong with either Dahlia or Scubb, then follow up with Kristin and her SoA/SoB combo. She isn't used in peoples' decks as often as I use her.

Pussycats: Emma. Nobody uses Emma. I was looking through the Pussycats and building a deck that didn't include Charlie or Ditha for once, so I opted for Emma and she won me a lot of ELO battles, and I made it into the high 1100s in only a short while. She is overlooked for the DR from Charlie, but she is a serious threat with the 12, even if she is used to bluff.
Rescue: Pam. There are a lot more threatening cards than Pam, but with all the bonuses and a 5 damage, Pam is good for forcing pill play.
Roots: Gertjan. Yes, I know it's a new card, but it's already so cheap and has a good ability in Mono use. Not a lot of people use Roots in mono, but they should.
Sakrohm: Nimestiec. Sometimes I see him, but he is a staple in my deck. I often open with him and people often forget how much AR he has, and they fall below. I love it, and he is a small 2* to pay, allowing Jautya and other heavy hitters in the deck.
Sentinels: Amy. I cannot count the number of times she is underestimated, and delivered a 7 damage (with fury). Love her! SoA is tragic, but she is still a good bluff and SoA is usually half decks.
Skeelz: Cley. People often dismiss Confidence-based abilities when building an ELO deck, and I think it's not always good to do so. Cley scares people, especially after being hit. Facing an 8/6, or even 8/8?? Good scare tactic.
Ulu Watu: Lucia. I am going with her because I have a thing for 6/6 cards, but also because a lot os SoA cards also have DR, both of which are no match!

Uppers: Stanford. He is underused, and a good way to get a quick 5 or even 7 damage on an opponent, who is holding out on pilling until against a more intimidating opponent.

Ula Wata - Kirk. He is alot better than Gaia but somehow people think Gaia is great when she isn't. Most of the 3 star ula wata are better. Kirk is awesome with his damage reduction.

People are going to bash me for this one, but...Estalt isn't that bad of a card! Since Kolos is banned, Estalt's 8 damage is the highest in the clan. Sure, there's Vinnie, but his 6 power is useless. Even though Estalt has 5 power, his power and bonus combined will bring almost all cards down to his level. Even if there's a card or two in the opponent's hand that is a power or attack manipulator, it's not that hard to play around them. There aren't that many cards with SOA as their ability: Striker, Elvira, the All Stops, and a few other ones are the only ones, out of hundreds of card, and it's unlikely that there are more than one in a hand.

Estalt's main problem is that he has to pill at least 1 more than the opponent (unless he's playing first and against another 5 star card). What I suggest doing is use him for his damage half the time, and as a scare/bluff card the other half. People will try and play around Estalt, meaning that it's really easy to predict their moves.

@catwomanMEOW
Gaia is liked for her playability at 1 and 2 stars. Not to mention she can do a decent chunk of damage at 3 star. More than Kirk at least. I agree that Kirk is underrated and a good card but thats no reason to write Gaia off so easily because she is a more than decent card. At least tied for second in 3 Star staples for Ulu (behind the all Mighty Nanook)