I think this is not a spoiler, because at market already say many times:
[i][b]a creature will keep only 60% of his age, will drop to lvl 1 (not just lose 1 lvl), will lose all wins and xp, but will keep tokens.[/b][/i]
[color="#FF0000"][b]ps: a transfer is a way to get crits you normally cant take at your own, or buy one with already some good amount of age/tokens...[/b][/color]