Puisque la FAQ répond autant s'en servir :
Arcane Laboratory
2U
Enchantment
Each player can't play more than one spell each turn.
Q: Can I play another spell during the same turn after Arcane Laboratory comes into play?
A: No. As soon as the Laboratory comes into play, it sees that you've already played one spell this turn (the Laboratory itself), so it won't let you play another one.
en traduction : tu ne pourras pas jouer d'autre sort puisque le laboratoire aura vu que tu auras déjà joué un sort ce tour ci : lui même (au minimum).