AncientMermaimon

[On Play] [When Digivolving] Return 1 of your opponent's level 4 or lower Digimon to the hand. For each of your other Digimon, add 1 to this effect's level maximum.
[All Turns] When this Digimon would leave the battle area, you may return to the hand or play 1 level 4 or lower blue Digimon card from this Digimon's digivolution cards without paying the cost .

[Alt]
DigiXros Requirements [DigiXros -2] [Lanamon] x [Calmaramon] 
When this would be played, you may place specified cards from your hand/battle area under it. Each one reduces the play cost.