I should start by confirming what Poppy Playtime is, its normal features, and then the Chapter 2 update that introduced Elmo. Next, explain what a mod is in this context. Then discuss the specifics of the Elmo mod. However, I need to be cautious here. The user is asking for a free download, which might be a pirated or modded version violating the game's terms. I have to highlight the legal and security risks of downloading such mods. Also, note that Google Play might not have this, so users are seeking third-party sources, which are unsafe.