He's probably a normal/ mack snow get tremper. If he was full tremper with Mack snow his eyes would be red and he'd look like a ether version of a tremper albino. Given that e looks more normal perhaps who bred him was confused and didn't realize you needed two sets of tremper genes in order to get an actual phenotypic tremper mack snow. If you breed him do so to a tremper and half the babies should come out to look like tremper albinos. That's how you'll know for sure