Does Heimerdinger gain access to Altar of Memories' ability since it has an exhaust effect, even though it doesn't have the explicit exhaust icon?

Ruling: Heimerdinger can only copy abilities that have the exhaust icon (symbol) at the start of the ability. If a card doesn't have the exhaust icon, Heimerdinger cannot copy it, even if the card exhausts as part of its effect.

Nuances:

• The exhaust symbol specifically represents exhausting as a cost (paid on activation), not exhausting as part of resolution
• Activated abilities use "cost : effect" structure where everything before the colon is cost
• Triggered abilities have effects (not costs in the same sense), and exhausting within a triggered ability happens on resolution, not activation
• Altar of Memories is a triggered ability that exhausts on resolution as part of its effect, not as an activation cost
• Heimerdinger is looking for abilities with the exhaust symbol, not just any effect that exhausts something at any point