Chimil, the Inner Sun's description states that "Cards in you hand can't have their mana drained or raised by effects your opponent control, except for Ward effects", which seems to imply that "friendly" mana drain effects such as Cycling or player-controlled creature effects should work. They, however, don't - Cycling ability is shown as red disabled icon altogether with Chimil on board regardless of how much mana I have in hand, and creatures like Tovolar, the Midnight Scourge will prompt to drain mana but then will drain none. Inability to drain mana for friendly effects makes it a much less interesting card. Additionally, the card text has a couple of typos ("in your hand", "opponent controls").
@Magic:PQ Support Team
Also when you play adversary (midnight hunt) creatures for example you are not asked to drain mana from your hand to get aditional effects
This is also preventing Urza's Fun House from being able to draft.