By casting Beck from the *Beck // Call* split card, you establish a replacement-style engine where every new creature entering the battlefield immediately replaces itself with a drawn card. That newly drawn card triggers Nadir Kraken, letting you feed just one generic mana back into it to drop a +1/+1 counter and spawn a 1/1 Tentacle creature token. As that Tentacle enters, Beck triggers to draw you another card, which you can fuel by feeding the Tentacle right into Ashnod's Altar for two colorless mana—leaving you plenty of profit to keep the loop going indefinitely.