102 - Uncanny X-Men Annual #18 - 4/12/1994

This is the issue where it's revealed that part of Kitty's uniform can turn into nunchuks.

Cover by Ian Churchill. Interiors by Glenn Herdling & Churchill

#XmenADay #XMen #XFactor40 #UncannyXMen #Annuals #Sabretooth #Caliban

092 - Uncanny X-Men #277 - 4/2/1991

This is the issue where Gambit gives Gladiator the full deck (not a euphemism).

Cover by Jim Lee. Interiors by Chris Claremont & Lee.

#XmenADay #XMen #XFactor40 #UncannyXMen #Gambit

091 - Uncanny X-Men #356 - 4/1/1998

The beginning of an O5/Phoenix story that doesn't end up going anywhere cuz Seagle leaves the book.

Cover by Chris Bachalo. Interiors by Steve Seagle & Bachalo.

#XmenADay #XMen #XFactor40 #UncannyXMen #Cyclops #JeanGrey #Angel #Beast #Iceman

007 - X-Cutioner

Probably the most successful of the characters introduced in these annuals - he made it into a cartoon - but Genis-Vell has him beat in terms of comic appearances.

Scans via tradingcarddb.com

#TradingCardADay #93A #UncannyXMen #XCutioner #XMen

087 - Uncanny X-Men #392 - 3/28/2001

The beginning of Northstar's first, brief, stint on the X-Men (Frenzy too, but she doesn't make the cover).

Cover by Salvador Larroca. Interiors by Scott Lobdell & Larroca

#XmenADay #XMen #XFactor40 #UncannyXMen #Northstar