> For the complete documentation index, see [llms.txt](https://docs.splinterlands.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.splinterlands.com/gameplay/types-of-cards/monsters.md). # Units Every card that is not a Summoner is classified as a Unit. While Summoners generally buff or debuff teams, Units are the foot soldiers of battle - taking damage and directly engaging with your opponent’s team. After selecting a Summoner for battle, you must select a team comprised of Units from the available elements. Your Units will fill the *Your Monsters* slots as indicated by the green box below.

All units have strengths and weaknesses. While some are useful for many situations, others are more niche and will only be called forth to play certain roles. ### **The components of Units include:** * [Rarity](https://docs.splinterlands.com/cards/card-rarities): The scarcity and relative strength of cards. * *There are four rarities: Common, Rare, Epic, and Legendary.* * [Mana Cost](https://docs.splinterlands.com/cards/card-stats/mana-cost): The numerical amount of Mana required to call a Unit to battle. * [Abilities](https://docs.splinterlands.com/cards/card-stats/abilities): Special skills that Units or Summoners possess. * [Element](https://docs.splinterlands.com/cards/card-stats/splinter): Units belong to one or two specific Elements (Fire, Water, Earth, Life, Death, or Dragon) or are Neutral. * [Stats](https://docs.splinterlands.com/cards/card-stats): The numerical indicators showing Speed, Strength of Attack, Health, and Armor * [Card Level & Base Card Experience](https://docs.splinterlands.com/cards/combining-cards): The strength of a card can be increased by combining copies of that same card into it.