Richard Garfield used this to design the games mana system and left this fun little credit to Larry Niven on Nevinyrral's Disk in the games original set
When you want to use this as a boardwipe, it will also wipe out your own creatures (unless Inspirit, Flagship Vessel is fully crewed), and for that, there are better options
Advanced Search Sets Random Syntax Showing 1-4 of 4 cards: "type: Creature, subtype: Cyberman" Display: Card Small Sorted By: Card Name Ascending Showing 1-4 of 4 cards: "type: Creature, subtype: Cyberman" Ashad, the Lone Cyberman Cyberman Patrol Cybermen Squadron The Cyber-Controller Advanced Search English
Won't your opponent just say the phrase everytime? they said, You're never going to get to draw the two cards. My response: One
Galadhrim Ambush Galadhrim Ambush is a very similar card to Arachnogenesis, and it'll probably be a green staple in EDH, particularly in elf decks
These are just a few of many that are possible