Ideally, decks are built with ink pairs that complement each other which the official Disney Lorcana Starter Decks do wonderfully
Its always on, and if a creature with toxic deals damage then the poison counters are inflicted without a trigger and without using the stack
Zurgo has an excellent baked-in ability, allowing him to attack, create a token, which is then sacrificed at the next end step, becoming a clever card draw tech
Other engines were more subtle, like Chief of the Edge supporting Khans non-wedge warrior theme or Legion Conquistador, Squadron Hawk, and Coldsnaps Ripple spells as single-card engines
See rule 702 rather than paying its mana cost. (See rule 708, Face-Down Spells and Permanents.) 702 rather than paying its mana cost and As this permanent is turned face up, put a +1/+1 counter on it if its megamorph cost was paid to turn it face up. A megamorph cost is a morph cost
As for March of Otherworldly Light, you all are aware of where I stand on that removal spell