Paleozoic Eldonia (SBC1-ENC20) [Speed Duel: Streets of Battle City]

Target 1 face-up monster on the field; it gains 500 ATK/DEF until the end of this turn. Once per Chain, when a Trap Card is activated while this card is in your GY: You can Special Summon this card as a Normal Monster (Aqua/WATER/Level 2/ATK 1200/DEF 0). (This card is NOT treated as a Trap.) If Summoned this way, this card is unaffected by monster effects, also banish it when it leaves the field.