I am very excited for this week's challenge as the Crypt Beatle is almost my always go-to when it comes to low mana battles. I have recently replaced my regular foil with gold foil too, go check him out!
You may have already realized the prices for regular foil cards have been increasing. There are still quite some good deals out there right now, especially when most people are trying to scoop up at least one copy of regular foil and preparing for the new reward changes. Go check him out before the prices go further up!
Let's first check out the stat of this week's protagonist: Crypt Beetle
Let me foreshadow that this is one of my favorite fights and crypt beetle was really the star here!
Anyway! Here is the battle link for my battle using Crypt Beetle: 
Let me share my reason for the team now.
The game has the following rulesets:
Heavy Hitters
Earth, Light, Death, and Dragon splinters can be chosen.
Mana limit: 16
When it comes to low mana battles, the first splinter I think of is death splinter as there are quite a lot of strong low mana monsters in death splinter. But if possible, I usually use Kretch to utilize the additional synergy between dragon and death monsters. Also, I had my Kretch maxed out, and it only costs 3 mana and provides better flexibility when creating our team, especially in this low mana battle.
I decided to go with the following team:
Summoner: Kretch
Crypt Beetle: Star of this fight! His shield ability, armor, and health make him an awesome tank for just 3 mana! In these low mana battles, there aren't a lot of high damage melee/ranged monsters that get effectively get through the shield ability. I have leveled him up to level 8 as well. His sustainability is wonderful. You can see in this fight that the enemy monsters have troubles trying to get through him. He's near invincible.
Corpse Fiend: 0 mana, 1 health, 1 melee damage. Perfect for low mana battles to take a hit from opportunity/snipe if there's any. Otherwise it'll still protect other monsters by taking any hits. In this situation, it's a very important monster because when Fiend dies, it'll give an extra health to another of my beloved monster---Riftwing.
Furious Chicken: My reason for picking furious chicken in this team is similar to corpse fiend's. Extra protection for other monsters, and also 1 extra health to Riftwing.
Riftwing: I often combine Crypt Beetle with Riftwing. Riftwing is one of my other favorites. I love the backfire as it dodges often with flying and its high speed. You can see Riftwing did quite some damage by dodging and backfiring, and also contributed by tanking a lot of damage.
Venari Bonesmith: 4 mana and 2 magic attack! Love life sapping to sustain for longer. Plus the poison ability is just a pain for the enemy.
Naga Assasin: 2 mana, 6 speed! For what this card offers, 2 mana is a steal! A lot of times it doesn't just do 2 damage each round, but so much more by dodging with its high speed and backfiring. I love to place her at the backline to "protect" other monsters while dealing consistent damage.
My team combination worked well I'd say! What do you think?
Hope you liked the battle. Let me know your thoughts on my team selection in the comments below.