To ensure I didn't make the same mistake I did when I summoned the Static Lightning, instead of googling the list and choosing what sounded cool, I made sure to read each description in full before making my choice.
[Rock Worm Larvae]
[Rank: F]
[Type: Task Force]
[Consumption: 1u/d]
[Diet: Minerals]
[Size: Tiny-Small]
[Description: Consumes a large amount of minerals everyday, it's able to grow multiple times it's size in a single day. When enough minerals have being consumed, it evolves to Rock Worm, Steel Worm, Copper Worm, Crystal Worm, Mud Worm or Sand Worm depending on its diet during its Larvae phase. ]
[Resources required]
-5 different minerals, 200g each
-Mana, 10u
"One glutton worm...Why is this classified as Task Force? Seems useless but at least its cheap."
[Diamond Spiderling ]
[Rank: D]
[Type: Defense Force]
[Consumption: 30u/d]
[Diet: Carnivore]
[Size: Tiny]
[Description: Highly poisonous. They are able to mimic Diamond gems to fool adventurers into holding them, giving them the opportunity to bite the holder's hand and poisoning them. Their body is very frail, but their high agility make them difficult to kill. It is said that at least one out of 5 diamonds found in Dungeons is a Diamond Spiderling.]
[Resources required]
-Diamond gems, 5
-Mana, 100u
"Why is this even here? Sure I have the gems. But! Not! Enough! Mana! The day I summon this is the same day I die." T_T
[Goblin Thief]
[Rank: E]
[Type: Defense Force]
[Consumption: 10u/d]
[Diet: Omnivorous]
[Size: Small]
[Description: Goblin thieves are experts in sneak attacks and stealing items from adventurers. They have an obsession for shinny things and are natural kleptomaniacs, targeting allies and enemies alike.]
[Resources required]
-Precious gems, 5kg
-Mana, 50u
"FIVE KILOGRAMS!? This is a theft! And this type of monster doesn't seem trust worthy at all!"
[Earth Sprite (egg)]
[Rank: F]
[Type: Task Force]
[Consumption: 0u/d]
[Diet: Mana]
[Size: Tiny]
[Description: Hatch after incubating for a week, giving birth to an Earth Sprite (baby). They are quite frail, please handle them with extra care.]
[Resources required]
-Topaz gem, 1
-Mana, 30u
"Hmm...completely useless until it hatch...Anyway, are eggs considered creatures??"
[Mud Golem (small)]
[Rank: F]
[Type: Defense Force]
[Consumption: 5u/d]
[Diet: Minerals]
[Size: Small]
[Description: Popularly known as Mud Slimes, they can manipulate earth with mana to create quicksand traps and try to suffocate their enemies with their bodies.]
[Resources required]
-Topaz gem, 3
-Clay, 10kg
-Blood drops, 10
-Mana, 30u
"This one seems like the most useful out of them, free traps sound nice but aside from that it looks inoffensive..."
All right, if I ignore what the creature does, the Worm Larvae and Earth Sprite Egg seems like my cheapest options. The spider is out of question, the goblin doesn't seem like a good idea... As for the Mud Golem, it seems useful the most useful, but I will have 1 day less if I summon it...
Let's take a look at their evolved versions! Maybe I'm being too optimist but since I have no better idea, I might as well do it.
"System, show me the Rock Worm status!"
[Understood!]
[Searching.]
[Searching..]
[Searching...]
[Found!]
[Rock Worm]
[Rank: C]
[Type: Task Force]
[Consumption: 90u/d]
[Diet: Minerals]
[Size: Medium-Big]
[Description: Popularly known as Mountain Destroyers. Rock Worms can digest up to 20 tons of rock per day, grinding them into sand.]
-Unavailable for Summon. Out of Stock.
"This....doesn't sound really good..."
[Steel Worm]
[Rank: B]
...
"Forget it!"
[Crystal Worm]
[Rank: S]
...
"No way!"
"You know what, Rock Worm Larvae are too dangerous! Let's take them out of the list!"
Maybe if this dungeon one day reaches C or B rank I will be able to afford them, but for now, no way!
"Ok, next candidate, Earth Sprite baby"
[Earth Sprite (baby)]
[Rank: E]
[Type: Task Force]
[Consumption: 10u/d]
[Diet: Vegetables]
[Size: Small]
[Description: Loved by farmers and alchemists, Earth Sprites are known for speeding up the growth of plants and multiplying the harvest.]
[Resources required]
-Topaz gems, 10
-Magical Vegetables, 10kg
-Mana, 120u
"Looks nice but I have no idea where I can get vegetables from...Well, I still have time to plant some before it hatches, maybe I will be able to improvise something..."
Last one...
[Mud Golem (medium)]
[Rank: D]
[Type: Defense Force]
[Consumption: 35u/d]
[Diet: Minerals]
[Size: Medium]
[Description: A bigger version of Mud Golem(small). Due to it's bigger size and mana pool it is many times more effective than it's smaller version. Unfortunately, due to it's slow movements, its attacks can be dodged easily even by creatures of lower rank.]
[Resources required]
-Topaz gem, 30
-Clay, 300kg
-Blood drops, 10
-Mana, 500u
"Looks strong! Well, at least for a D rank monster..."
I would have no problem with it's food but its Mana Consumption is a bit of a problem...
Well, if I remember it right Mud Golems should take some time to grow so I won't have to worry about it anytime soon...
Ok, the options are down to Mud Golem and Earth Sprite. Both options seem good...What to do...
I wish there was a dice or something so I could just leave it to destiny...
Wait! If there is none, all I need to do is create one!
"Building mode!"
[Understood!]
...
I put my hand on the floor, filled my palm with mana and pushed it up, creating a pillar. Then I slowly sculpted a dice on the pillar. Finally I cut of the dice from the pillar, finishing my gambling tool.
"Well, this may not be perfect, but considering I had no tools, this seems pretty good!"
"Let's see... if it fall below 4 I will summon the Earth Sprite, if it falls above 3 I will summon the Mud Golem..."
Finally, leaving it in the hands of Fate, I rolled the dice.
Roll...
Roll...
Roll...
Stop...
"And so Fate has decided!"
Quickly tapping the Summon command before I could have cold feet.
"Little friend, I choose you!"
A ray of light appears from below and as it vanished I saw the Creature standing right in front of me.
[Summoning Complete!]