Or, you can skip all of that trickiness and just have an evasive Sliver in play, letting you attack with just one or two creatures and leaving the rest of your army back to block
If you cast a spell "without paying its mana cost," you can't choose to cast it for any alternative costs
Ulalek will not copy ETB triggers
There are three primary ways to win with tokens: You attack with enough creature tokens that your opponent cant possibly hope to block them all, You pair your token generation with Mirkwood Bats, Impact Tremors, Zulaport Cutthroat, and similar effects that drain your opponents life total as your tokens enter and leave the battlefield, or You have sacrifice outlets that let you cash in tokens to kill blockers and/or drain your opponents life, like Goblin Bombardment
the potential to buff your board while also being an unfavorable block target is reminiscent of some classic Magic design a la enchanting a Whirling Dervish with Venom