So, it's possible you can trigger an effect four times with just one activation with Katara and the right mix of effect doublers on the battlefield
Pawpatch Recruit and Surrak, Elusive Hunter punish opponents for going after your creatures
Other than shuffling the rest of your deck afterwards, there's no extra cost to this
Alelas lifelink matches nicely with the lifegain/life drain that bats often play into, and I guess you can add some auras and equipment that increase the power of your lifelinkers, give them double strike and other relevant abilities
Here are all of the cards in the 'Mega Rising Museum 6' Secret Mission: Whimsicott ex #273 (Rainbow / Two Gold Star) Mega Ampharos ex #277 (Rainbow / Two Gold Star) Indeedee ex #278 (Rainbow / Two Gold Star) Tauros ex #283 (Rainbow / Two Gold Star) Rewards: 36 Wonder Hourglasses, 12 Pack Hourglasses and 10 Shop Tickets
When you'll add the new Set