Line large cookie sheet with waxed paper or cooking parchment paper. To make 20 butterflies, arrange pretzel twists on cookie sheet in groups of 2 with single-hole sides of pretzels touching to form butterfly wings (see diagram). Break remaining 5 pretzels into pieces for antennae; place 2 pieces at top of each butterfly between wings.
In 1-quart resealable freezer plastic bag, place vanilla chips and oil. Microwave on High 1 minute 20 seconds or until melted, squeezing bag to mix. Seal bag; cut small hole in 1 corner of bag.
Squeeze bag to pipe thin zigzag of melted chips between pretzels to look like bodies of butterflies. Press pretzel pieces firmly into melted chips. Pipe melted chips into each hole in wings; top each with 1 candy. Let stand until set, about 30 minutes. Remove from waxed paper; store in tightly covered container.