I recently came across a post by @rentmoney talking about their favorite Splinterlands card and asking about other people's favorites. Since then, I spent some more time to think about that question and decided to share some thoughts and information about my favorite card in this post.
Also, feel free to check out the original post which inspired me to think about this question.

Since I usually play modern, I have to admit that my favorite card in the game changes rather frequently and depends a lot on the current playable cards and meta.
At first, my mind went to Kaylia Silverleaf as my favorite card, because at the moment I play it almost every chance I get. Although, Kaylia is definitely my favorite Archon at the moment, after some more thinking and playing a few matches I remembered another card that I love to play and that has a very unique and cool ability, in my opinion.

Lore

Although I usually don't care too much about the Lore within Splinterlands, I do think it is great to have some lively stories behind the characters of the game. In my opinion the SPL team does a great job at bringing the universe of Praetoria to life and therefore I wanted to include at least a short summary of Olivia's Lore in this post.

Olivia is a Druid from the Kingdom of Lyveria. Her father, also a Druid, was conscripted into the Legions of the Chaos Empire and sacrificed his freedom to make sure his daughter could escape. She spent her time living in the woods, practicing druidic magic until she was powerful enough to start striking at the Chaos Empire and aiding oppressed townsvolk and villagers with supplies. This led to her becoming a symbol of freedom and the Empire putting a bounty on her.
Last but not least, my favorite part about Olivia's Lore: As seen on the picture above, Olivia is not on her own, but has a loyal companion with her.
A snow leopard named Cloudy!

Card stats

The first thing that makes Olivia a great card, when considering the stats, is the dual magic and melee attack power. Although it's just 1 magic and 1 melee attack at level 1, it's still pretty strong. Especially with the opportunity ability, which it already has at level 1 as well. It can sometimes kill some strong backline units with low Health or maybe just chip away the armor for other units to deliver a killing blow afterwards. With only 4 health Olivia is quite squishy herself at level 1, so she probably needs some additional protection from other cards. At max level she's not super tanky with her 6 Health and 1 Armor, but it might be enough for her to be able to take a hit or two. The Deflect ability at level 6 should also help her to stay alive as long as possible.

Mimic
Now to the main selling point of this card. The Mimic ability.

At the beginning of round 2 and each following round, gain a random ability from the enemy team. Dispel removes one mimicked ability in the order they were gained. Debilitations, Targeting abilities, Ambush, Weapons Training, Flank, Reach, Charge, and Taunt cannot be mimicked

At the moment, Olivia of the Brook is one of only two cards with this ability in the game (Palifala Weslinath being the other one). Since it has been introduced, this has been by far my favorite ability in the game. It can make so many battles way more interesting, because it's not just about picking a strong team yourself anymore but also considering the enemy's team and their abilities.
If placed in a smart way and protected for long enough, Olivia can turn into an absolute beast by taking several abilities from enemy units. However, as strong as it sounds at first, it doesn't make the card overpowered.
Without additional protection, it can quite easily get killed by enemy units with Opportunity. In addition to that, not all abilities are beneficial if they are taken from enemy monsters.

That's also big part of the reason, why Olivia of the Brook is my favorite card in the game at the moment. It has a lot of potential but is not overpowered. It can easily carry your whole team to victory if played in a smart way but it can also turn out to be quite useless when killed too early or stealing the wrong ability.

Battles

Since I didn't have a lot of time to play in the last weeks, I didn't get a lot of battles done in general. However, I still managed to get a few battles with Olivia to show her potential and also how she can get herself killed by stealing the wrong ability.


https://splinterlands.com/battle/sl_9167d94ddafe03853bbc784e363c0e5b

I think this battle shows the potential of Olivia pretty good. She immediately eliminates Grifzi in the first round, already removing some damage from the enemy team. It also shows, that positioning can be rather important, as in this battle I mainly picked the Quokka so that it gets attacked by units with Opportunity instead of them attacking Olivia. Later on in the battle, when Olivia ends up in first position, she also has the Demoralize ability, which weakens the enemy team so she can't get killed anymore.


https://splinterlands.com/battle/sl_e7d0baa809ee76718572a490ab10bcc6

Although Olivia is does not seem that effective in this battle, I still decided to put it in here because it highlights that Olivia can possibly acquire very powerful abilities like Halving from the Henchling Enforcer. In combination with the Aimless ruleset, this is a very strong ability that could easily weaken the whole enemy team.


https://splinterlands.com/battle/sl_d234fa32daf216080567e0d462982aba

This battle actually shows one of the worst enemies for the units with the Mimic ability, the Night Reaper. Here at the beginning of Round 3, the worst case happens and Olivia steals the Flying ability. This of course makes her the target of the Night Reaper's Wingbreak ability, killing her instantly. To be honest I don't know if stealing another ability would've changed the outcome of this battle. I definitely had some battles before, though, where I lost just because of Olivia stealing the Flying ability from Night Reaper.