Check out the D&D board games. Each comes with 30-50 minis and costs $40-50.

There are also a variety of things like this:

https://www.amazon.com/dp/B00W5WSN5A/ref=cm_sw_r_cp_apa_iBKwAbE208QG2

Like this one: https://www.amazon.com/SCS-Direct-Monster-Action-Figure/dp/B00W5WSN5A/ref=pd_aw_fbt_img_2/134-8880743-4838965?_encoding=UTF8&pd_rd_i=B00W5WSN5A&pd_rd_r=a5951613-b766-4f20-b536-e54887713235&pd_rd_w=CATo6&pd_rd_wg=YEgRR&pf_rd_p=83a505b9-cf12-49d3-b4b0-71c1b82f4248&pf_rd_r=MYS84ZJKMVNHMSVQT7TR&psc=1&refRID=MYS84ZJKMVNHMSVQT7TR

SCS Direct Monster Mini Action Figure Playset- 100 Horror Toy Miniatures w 13 Unique Sculpts - Dracula, Frankenstein, Giant Spiders and More- XL 1/32nd Scale Character Accessories https://www.amazon.com/dp/B00W5WSN5A/ref=cm_sw_r_other_apa_i_1Z79EbWVD1X7P