I currently rent the lowest priced cards to increase my collection power to the Silver III level. When I see cards with different abilities in lineups, I usually make a note especially if that lineup beats mine.
A common card I added to my deck after I noticed that I used it almost every time when I create a Life Splinter lineup was the Silvershield Knight which has the Inspire ability (+1 Melee to all Friendly). I liked it so much that I purchased the Beta as an investment thinking that when Splinterlands changes the standard card pack for users to Untamed and Chaos, they may add Beta cards to the 10% bonus for match wins. But this is only a wish since I have no clue what they will be doing. I use it so much that I am renting the Alpha to get the 10% bonus for match wins. That rental is paying for itself plus some to cover other rentals.
Of Common cards that I have never used the Baby Unicorn seems to have a useful ability of adding health to friendlys. I have only seen it in lineups a few times so do not know how useful it may be. I just like the graphics as it catches my eye every time it is played against me. It is an interesting low mana card that I do not own or rent. It would probably be a nice common card to add and use with the above Silvershield Knight.
The silvershield knight is definitely a nice card to have especially when you combine it with melee cards that have the sneak ability. It's very powerful in low level leagues. The baby unicorn is also very interesting. I play it actually quite often because at a higher level it also give the Swiftness ability to the whole team. This is one more life and more speed to all the cards. This can make a big difference.
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