Ive seen players show up to tournaments with fake cards, thinking they got the real thing at a bargain
Kaiba attacked "Dark Paladin" with "Blue-Eyes Ultimate Dragon", but Dark used "De-Fusion", splitting the "Ultimate Dragon" into three "Blue-Eyes White Dragons"
For three mana, it lets you destroy all creatures that entered the battlefield that turn - or you can exile a black card from your hand to play it for free
This Pokemon Tool might not scream ultra-powerful, but it does provide rather important utility in a future card-themed deck

THEGIANTSHADOW Purple Purchase Purchase on TCGplayer ($71.81) Main Deck (50) x4 $0.19 x4 $0.10 R1 $0.61 x3 $0.29 x2 $0.16 R1 $0.62 x4 $0.21 $0.13 x4 $0.68 x4 $1.20 x4 $10.44 x4 $11.43 R1 $0.13 x3 $0.62 x4 $1.46 x2 $0.18 x2 $0.18 x2 $0.24 Egg Deck (4) x4 $0.20 Digimon (36) 4 Goblimon BT14-070 $0.19 Lv.3 2000 3 Ignitemon BT11-076 $0.29 Lv.3 2000 4 Tsukaimon EX7-052 $0.10 Lv.3 1000 1 Ukkomon P-123 $0.61 Lv.3 2000 2 BlackGatomon EX7-054 $0.16 Lv.4 3000 1 Dobermon (X Antibody) EX5-059 $0.62 Lv.4 4000 1 Ginkakumon Promote BT6-075 $0.13 Lv.4 6000 4 Witchmon EX6-048 $0.21 Lv.4 4000 4 LadyDevimon BT3-088 $0.68 Lv.5 8000 4 LadyDevimon (X Antibody) EX7-058 $1.20 Lv.5 8000 4 Lilithmon EX6-057 $10.44 Lv.6 11000 4 Lilithmon (X Antibody) EX7-061 $11.43 Lv.6 12000 Option (12) 1 Jack Raid BT4-111 $0.13 2 Phantom Pain EX6-070 $0.18 3 Purple Scramble LM-032 $0.62 2 Seventh Fascination EX7-072 $0.18 4 Wisdom Training P-108 $1.46 Tamer (2) 2 Matt Ishida ST16-14 $0.24 Egg Deck (4) 4 Tsunomon BT6-006 $0.20 Lv.2 Card Types Digimon 36 Option 12 Digi-Egg 4 Tamer 2 Levels Lv.3 12 Lv.4 8 Lv.5 8 Lv.6 8 Lv.2 4 Colors Purple 53 White 1 Play Cost 0 Cost 1 2 Cost 7 3 Cost 9 4 Cost 9 5 Cost 5 6 Cost 1 7 Cost 2 8 Cost 8 11 Cost 4 12 Cost 4 Traits Seven Great Demon Lords 10 X Antibody 9 Fallen Angel 8 Demon Lord 8 Demon 5 Mammal 4 Wizard 4 Reptile Man 3 Blocks Block 00 5 Block 01 5 Block 02 12 Block 03 21 Block 04 20 Purple Necro BT23 was so bad, I'm adding bt26 chirop

Below 4, even an S/R-rated combo gets downgraded to Bracket 3 because the deck lacks the support to deploy it consistently