thinking fondly back on my favourite deck i've ever done in tcg, which is when i made the bat factory in Eternal

basically i had a creature which part of its effects gave everything on the battlefield +1/+1 whenever i gained life
Combined with bats which were low cost fliers with lifesteal and a creature that made more bats every turn, I could make an army of swole bats

It probably wasn't good per se but it was really fun when it worked