Robby Roto - MAME - Puzzle

When playing this game. YOU are ROTO's mentor. He takes his directions ONLY from YOU and will do your bidding exclusively. YOU determine the strategies he will use to defeat the evil monster VOLTAR who has invaded the Earth, stealing all types of treasures and burying them deep within the earth. VOLTAR also takes hostages and seals them in vaults deep within the earth. There is only one way to save the hostages and recover the stolen treasures. We must send in ROTO. He will follow VOLTAR right into his own home tunnels to rescue the hostages and recover the stolen treasures VOLTAR has salted away. To say the least, this makes VOLTAR more than just a little bit upset with ROTO. To help protect his stolen treasures and kidnapped hostages. VOLTAR has developed a breed of giant SPIDER that can sense ROTO's location and that can also travel through solid earth. These SPIDERS attempt to corner and capture ROTO. And to direct their hunt for ROTO, VOLTAR turns himself into a TROLL that can travel through solid earth.