Link

When Link enter the battlefield, merge together
2 or 3 creature. Put a token over them. The total
mana cost of all the merging creature must not
exceed 5. (Power and Toughness
add up and skills too)
To exceed 5 mana cost, sacrifice 1 Positive Energy
Generator with 5 Positive {e}. Create 5 token
True Hero. Sacrifice them all and put New Hero
token on the battlefield with the correct
amount of Power and Toughness.